JP2017141505A - Apparatus for manufacturing molded article and method for manufacturing molded article - Google Patents

Abstract

Provided are a manufacturing apparatus and a manufacturing method capable of manufacturing a three-dimensional object by additive manufacturing at a low cost even with a metal powder material having a low absorptance of near infrared wavelength laser light. A manufacturing apparatus 100 is an apparatus for manufacturing a modeled object that is solidified by sintering or melting a metal powder 15 by irradiation with a modeling light beam L1, and irradiates a chamber 10 and the metal powder 15 with an irradiation range Ar1. The metal powder supply device 20 for supplying to the metal powder, the modeling light beam irradiation device 30 for irradiating the metal powder 15 in the irradiation range Ar1 with the modeling light beam L1, and the absorptance for performing a predetermined absorptivity improvement supporting process on the metal powder 15. After implementation of the improvement support unit 40 and the absorption rate improvement support process, the modeling unit 70 that performs the modeling process of irradiating the modeling light beam L1, heating the metal powder 15, solidifying by sintering or melting, and performing layered modeling. Prepare. [Selection] Figure 1

Description

  The present invention relates to a manufacturing apparatus and a manufacturing method for manufacturing a layered object using metal powder as a raw material using laser light.

  In recent years, development of metal AM (Additive Manufacturing) has been actively developed in which a powdered metal is sintered or melted by laser light irradiation to be solidified and layered one by one to produce a three-dimensional shaped object. Yes. In such a metal AM, not only trial production but also examination for mass production has begun. The metals used in the metal AM include maraging steel, stainless steel (SUS), which can be manufactured at low cost because the absorption rate of near-infrared wavelength laser light, which is mainly inexpensive laser light, is good. Examples include titanium steel (Ti).

  However, in the market, as metal powder material of metal AM, not only maraging steel, stainless steel (SUS), and titanium steel (Ti), but also copper and aluminum having a low absorption factor of laser light of near-infrared wavelength. There is a strong demand for adoption. On the other hand, Patent Document 1 discloses a metal AM technique in which the metal powder material is aluminum. In the technique of Patent Document 1, a laser absorbent having a high absorption rate of near infrared wavelength laser light is included in aluminum powder. Thus, when near-infrared wavelength laser light is irradiated, the near-infrared wavelength laser light is first absorbed and heated by the laser absorber, and the heat is conducted to the aluminum powder to heat the aluminum powder. Keep warm together. In such an environment, it is described that the aluminum powder is further heated and melted by irradiation with laser light having a near infrared wavelength and heat from a laser absorbent.

JP 2011-21218 A

  However, in the technique of Patent Document 1, the laser absorbent itself may cause a cost increase. Further, the laser absorber mixed with the aluminum powder becomes an impurity, which may adversely affect the strength of the product.

  The present invention has been made in view of the above problems, and is capable of producing a three-dimensional structure by additive manufacturing at a low cost even with a metal powder material having a low absorption rate of laser light of near-infrared wavelength. An object is to provide an apparatus and a manufacturing method.

  In order to solve the above-mentioned problem, a manufacturing apparatus for a model according to claim 1 of the present invention is a manufacturing apparatus for a model that solidifies and sinters metal powder by sintering or melting by irradiation with a modeling light beam, A chamber capable of shutting off outside air and inside air, a metal powder supply device that is provided inside the chamber and supplies the metal powder to the irradiation range of the modeling light beam, and the inside of the chamber supplied to the irradiation range A modeling light beam irradiation device for irradiating the metal powder with the modeling light beam, and a predetermined absorption rate improvement with respect to the metal powder in order to improve the absorption rate of the irradiated modeling light beam into the metal powder. An absorption rate improvement support unit that performs support processing, and after execution of the absorption rate improvement support processing, the modeling light beam is irradiated to the metal powder supplied to the irradiation range, and the metal powder is heated. , And a shaping part for performing modeling process of the layered manufacturing solidified by the sintering or the melt.

  As described above, the manufacturing apparatus for a shaped article irradiates the metal powder with the modeling light beam after performing the absorption rate improvement supporting process for increasing the absorption rate of the modeling light beam with respect to the metal powder by the absorption rate improvement supporting unit. For this reason, the modeling light beam is well absorbed by the metal powder. Therefore, since the metal powder is heated well and solidified by sintering or melting by the irradiation of the modeling light beam for a short time, the time for the layered modeling can be shortened, and the modeled object can be manufactured at a low cost.

  Moreover, the manufacturing method of the molded article according to claim 23 of the present invention is a manufacturing method of a molded article that is solidified by sintering or melting and stratified modeling by irradiation of a modeling light beam, and the metal powder is A metal powder supplying step for supplying to the irradiation range of the modeling light beam and a predetermined absorption rate improvement support process for the metal powder in order to improve the absorption rate of the irradiated modeling light beam to the metal powder. After carrying out the absorption rate improvement support step and the absorption rate improvement support process, the modeling light beam is irradiated to the metal powder supplied to the irradiation range, the metal powder is heated, and the sintering or the melting is performed. And a modeling step of performing a modeling process for solidifying and layering. Thereby, the modeling thing similar to the modeling thing manufactured in Claim 1 can be manufactured.

It is a schematic diagram of the manufacturing apparatus which concerns on 1st, 2nd embodiment. It is a top view of the metal powder supply apparatus in FIG. It is a graph which shows the relationship between the wavelength of near infrared laser beam according to metal material, and an absorptance. It is a partial perspective view of the modeling light beam irradiation apparatus in FIG. It is a schematic diagram explaining the state in which the oxide film was formed on the surface of the thin film layer. It is a graph which shows the relationship between the film | membrane pressure of the oxide film with respect to copper, and the absorption factor of a near-infrared laser beam. It is a flowchart 1 of the manufacturing method which concerns on 1st embodiment. It is a figure which shows the state of irradiation of the short wavelength laser beam in the pre-heating process of FIG. It is a figure which shows the state of irradiation of the near-infrared laser beam and short wavelength laser beam in the oxide film formation process of FIG. FIG. 8 is a diagram showing a state in which oxide films are formed at a plurality of places in the oxide film forming process of FIG. 7. It is a figure explaining the state of irradiation of the near-infrared laser beam in the modeling process of FIG. In the modeling process of FIG. 7, it is a figure which shows the state in which the solidified thin film was formed in several places. In 2nd embodiment, it is a figure which shows the state of irradiation of the near-infrared laser beam and short wavelength laser beam in an oxide film formation process. In 2nd Embodiment, it is a figure which shows the state of irradiation of the near-infrared laser beam in modeling processing. It is a figure which shows the state of irradiation of the near-infrared laser beam and short wavelength laser beam in the oxide film formation process of 3rd embodiment. It is a schematic diagram of the manufacturing apparatus which concerns on 3rd embodiment. It is a flowchart 2 of the manufacturing method of 3rd embodiment. It is a figure which shows the state of irradiation of the near-infrared laser beam in the oxide film formation process of 3rd embodiment. It is a figure which shows the state which formed multiple oxide films in the oxide film formation process of 3rd embodiment. It is a figure which shows the state of irradiation of the near-infrared laser beam in the modeling process of 3rd embodiment. It is a schematic diagram of the manufacturing apparatus which concerns on 4th embodiment. It is a schematic diagram of the manufacturing apparatus which concerns on 5th embodiment. It is a flowchart 3 of the manufacturing method of 5th embodiment.

<1. First embodiment>
(1-1. Overview)
An apparatus for producing a three-dimensional structure (corresponding to a structure) according to the present invention will be described with reference to the drawings. The apparatus for manufacturing a three-dimensional structure is an apparatus for laminating a three-dimensional structure by solidifying the metal powder 15 by sintering or melting mainly by irradiation with a modeling light beam, which will be described in detail later. In the present embodiment, the modeling light beam is near-infrared wavelength laser light, and is hereinafter referred to as near-infrared laser light L1.

  In addition, as the metal powder 15, a “low-absorbance material” whose absorption rate of near-infrared wavelength laser light at normal temperature is a predetermined value or less is targeted. At this time, the predetermined value is, for example, an absorption rate of 30% (see FIG. 3). In this case, copper, aluminum, or the like is targeted as the “low absorption rate material”, and in the following embodiments, copper powder that is copper powder will be selected and described as the metal powder 15. Moreover, in this embodiment, when carrying out the layered modeling of a three-dimensional modeled object, it demonstrates as what solidifies by solidifying the metal powder 15 not by sintering but carrying out the layered modeling. Note that the three-dimensional structure may be manufactured not by melting but by sintering.

(1-2. Manufacturing apparatus 100)
FIG. 1 is a schematic diagram of a manufacturing apparatus 100 according to the first embodiment of the present invention. The manufacturing apparatus 100 includes a chamber 10, a metal powder supply device 20, a modeling light beam irradiation device 30, an absorption rate improvement support unit 40, a support light beam irradiation device 41, and a modeling unit 70. The absorption rate improvement support unit 40 and the modeling unit 70 are provided in the control unit 45. The absorption rate improvement support unit 40 includes a laser light irradiation control unit 49, a film thickness estimation unit 50, and a process switching determination unit 60.

The chamber 10 is a casing formed in a substantially rectangular parallelepiped shape, and is a container capable of blocking outside air and inside air. The chamber 10 includes a device capable of replacing the internal air with an inert gas such as He (helium), N ₂ (nitrogen), or Ar (argon) (not shown). It should be noted that the chamber 10 may be configured to be able to be depressurized instead of replacing the inside with an inert gas.

  The metal powder supply device 20 is provided inside the chamber 10 and applies the metal powder 15 that is a raw material of the three-dimensional structure to the irradiation range Ar1 (see FIG. 2) of the near-infrared laser beam L1 (corresponding to the modeling light beam). Supply. The metal powder 15 is a copper (Cu) powder. In addition, the metal powder 15 here means the aggregate | assembly which a plurality of each copper powder gathered.

  As shown in FIGS. 1 and 2, the metal powder supply device 20 includes a modeling container 21 and a powder container 22. As shown in FIG. 1, a modeling object lifting table 23 is provided in the modeling container 21. A thin film layer 15 a of the metal powder 15 is formed on the model lift table 23. Then, the metal powder 15 of the thin film layer 15a is melted mainly by irradiation of the near infrared laser light L1 to the thin film layer 15a, and then solidified to form the solidified thin film layer 15b. Next, the model lift table 23 is moved downward, and the thin film layer 15a is formed again in the same manner as described above. The metal powder 15 of the thin film layer 15a is melted mainly by irradiation of the near infrared laser light L1 to the thin film layer 15a, and then solidified to form the solidified thin film layer 15b again. Laminate on top. A three-dimensional structure is produced by repeating such operations.

  In the powder container 22, the metal powder 15 is stored on the feed table 24, and the metal powder 15 is supplied by moving the feed table 24 upward. Note that support shafts 23a and 24a are attached to the model lifting table 23 and the feed table 24, respectively. The support shafts 23a and 24a are connected to a drive device (not shown) and are moved up and down by the operation of the drive device.

  Further, a recoater 26 that moves over the entire area of the opening of the modeling container 21 and the powder container 22 is provided. The recoater 26 moves from the right to the left in FIGS. As a result, the metal powder 15 supplied by the ascent of the feed table 24 is conveyed onto the shaped article lifting table 23, and the thin film layer 15 a of the metal powder 15 is formed on the shaped article lifting table 23. The thickness of the thin film layer 15 a is determined by the descending amount of the model lifting table 23. In the present embodiment, the thin film layer 15a has a thickness of about 50 μm to 100 μm. However, this thickness is only an example and is not limited to this thickness.

  The modeling light beam irradiation device 30 irradiates the surface of the thin film layer 15a of the metal powder 15 in the chamber 10 supplied to the irradiation range Ar1 (see FIG. 2) by the metal powder supply device 20 with the near infrared laser light L1. . As shown in FIG. 1, the modeling light beam irradiation device 30 includes a laser oscillator 31 and a laser head 32. The laser oscillator 31 includes an optical fiber 35 that transmits the near-infrared laser light L1 oscillated from the laser oscillator 31 to the laser head 32.

  The laser oscillator 31 generates a near-infrared laser beam L1 that is a laser beam of a continuous wave CW by oscillating so as to have a predetermined near-infrared wavelength. The wavelength of the near infrared laser beam L1 is around 1.0 μm. Specifically, as the near-infrared laser beam L1, HoYAG (wavelength: about 1.5 μm), YVO (yttrium vanadate, wavelength: about 1.06 μm), Yb (ytterbium, wavelength: about 1.09 μm) and fiber A laser or the like can be used. As a result, the laser oscillator 31 can be manufactured at low cost, and energy consumption is small and inexpensive even during operation. In addition, as shown in FIG. 3 showing the relationship between the wavelength (μm) of the laser beam for each material and the absorption rate (%) of the laser beam, the near-infrared laser beam L1 has a relatively high absorption rate for copper and aluminum. It is low and the absorption rate is 30% or less.

As shown in FIG. 1, the laser head 32 is disposed at a predetermined distance α from the surface of the thin film layer 15a of the metal powder 15 in the chamber 10 and at a predetermined angle α ° with respect to the vertical direction. .
As shown in FIG. 4, the laser head 32 includes a collimating lens 33, a mirror 34, a galvano scanner 36, and an fθ lens 38. The collimating lens 33, the mirror 34, the galvano scanner 36, and the fθ lens 38 are disposed in the housing of the laser head 32. The collimating lens 33 collimates the near-infrared laser light L1 emitted from the optical fiber 35 and converts it into parallel light.

  The mirror 34 changes the traveling direction of the near-infrared laser beam L1 so that the collimated near-infrared laser beam L1 enters the galvano scanner 36. In the present embodiment, the mirror 34 converts the traveling direction of the near-infrared laser light L1 by 90 degrees.

  The galvano scanner 36 changes the traveling direction of the laser light L and irradiates the near infrared laser light L1 to a predetermined position on the surface of the thin film layer 15a through the fθ lens 38. That is, the laser head 32 can freely change the irradiation angle of the near-infrared laser beam L1 oscillated from the laser oscillator 31 by the galvano scanner 36. The predetermined position where the near-infrared laser beam L1 is irradiated will be described in detail later. As the galvano scanner 36, for example, a known scanner including a pair of movable mirrors (not shown) capable of swinging in two orthogonal directions is used. The fθ lens 38 is a lens that condenses the parallel laser light L incident from the galvano scanner 36. Further, the laser light L emitted from the laser head 32 is irradiated into the chamber 10 through transparent glass or resin provided on the upper surface of the chamber 10.

  The absorption rate improvement support unit 40 is a control unit that performs the absorption rate improvement support process using the above-described near-infrared laser beam L1 (modeling light beam) and the short wavelength laser beam L2 (supporting light beam) described later. Provided in the controller 45 (see FIG. 1). The absorption rate improvement support unit 40 can take various predetermined means (absorption rate improvement support processing). However, in the first embodiment, the process of forming the oxide film OM having a predetermined thickness on the surface of the thin film layer 15a of the metal powder 15 is referred to as an absorption rate improvement support process.

  With this process, the absorption rate of the near-infrared laser beam L1 with respect to the metal powder 15 (copper powder) can be improved in a modeling process described later, which is performed after the absorption rate improvement support process. The irradiation of the near-infrared laser beam L1 (modeling light beam) and the short wavelength laser beam L2 (supporting light beam) is controlled by the laser beam irradiation control unit 49.

  Although details of the short wavelength laser beam will be described later, for the sake of explanation, a brief description will be given here. The short wavelength laser beam L2 is a laser beam having a short wavelength (for example, a wavelength of 0.2 to 0.6 μm) whose wavelength is shorter than the near infrared wavelength. In the present embodiment, the short wavelength laser beam L2 is a continuous wave CW laser beam. Looking at FIG. 3 showing the relationship between the wavelength (μm) of the laser beam and the absorption rate (%) of the laser beam by material, the absorption rate of the short wavelength laser beam with respect to copper is higher than the absorption rate of the near infrared laser beam. high. Examples of the short wavelength laser include a UV laser, a green laser, and a blue laser. In the first embodiment, for example, a blue laser is applied.

  In the first embodiment, the absorption rate improvement support process performed (controlled) by the absorption rate improvement support unit 40 is performed on the surface of the thin film layer 15a following the preheat treatment on the surface of the thin film layer 15a and the preheat treatment. An oxide film forming process. First, in the preheat treatment, the surface of the thin film layer 15 a is irradiated with a short wavelength laser beam L 2 (supporting light beam) having a high absorption rate with respect to the metal powder 15 (copper powder) under the control of the short wavelength laser beam irradiation unit 46. By this irradiation, the surface of the thin film layer 15a of the metal powder 15 in the chamber 10 which is the irradiation position is heated to, for example, 600 ° C. to 800 ° C. which is lower than the melting point (1060 ° C.) of copper. At this time, the oxide film OM is not yet formed on the surface of the thin film layer 15a at the irradiation position.

  As shown in FIG. 3, the short-wavelength laser light L2 inherently has a high absorptivity with respect to copper, so that it can be sufficiently heated even at a low output. Thereby, even the short wavelength laser light L2 can heat (preheat) the surface of the thin film layer 15a at a relatively low cost. Next, in the oxide film forming process, the surface of the thin film layer 15a is heated (preheated) and the base temperature is raised, and the short wavelength laser light L2 and the near-infrared laser light L1 are simultaneously superimposed and irradiated. An oxide film OM is formed on the surface.

  In the above, the purpose of preheating the surface of the thin film layer 15a is to make it easier to form the oxide film OM on the surface of the thin film layer 15a in the oxide film forming process. That is, the base temperature of the thin film layer 15a increases due to preheating. For this reason, when the short wavelength laser beam L2 and the near-infrared laser beam L1 are simultaneously superimposed and irradiated, it is possible to reduce the width of the temperature to be raised before the formation of the oxide film OM. Therefore, it is possible to shorten the superimposition irradiation time of the short wavelength laser beam L2 and the near infrared laser beam L1, and it is possible to form the oxide film OM in a short time with a low output.

  In addition, it is known that in copper, the absorption rate of the near-infrared laser light L1 is improved near the melting point, and an oxide film OM (cuprous oxide) is formed on the irradiated surface. For this reason, the surface of the thin film layer 15a is preheated to 600 ° C. to 800 ° C. by irradiation with the short wavelength laser light L2, so that the irradiation with the superposition irradiation with the short wavelength laser light L2 and the near infrared laser light L1 in the oxide film forming process is performed. Time and output (required energy) can be suppressed satisfactorily. As described above, in the first embodiment, the surface of the thin film layer 15a is preheated by irradiating the short wavelength laser light L2, and the surface of the thin film layer 15a that is preheated and kept in the heat retaining state is The oxide film forming process for forming the oxide film OM by superimposing the short-wavelength laser light L2 and the near-infrared laser light L1 is an absorption improvement improvement process.

  Here, the relationship between the absorption rate of the near-infrared laser beam L1 with respect to copper and the film thickness of the oxide film OM will be described. As shown in FIG. 5, when the oxide film OM is formed on the surface of each copper powder of the metal powder 15, the near infrared laser light L1 irradiated toward the oxide film OM transmits or oxidizes the oxide film OM. While reflecting inside the film OM, it is efficiently absorbed by the surface of the copper powder and heats the copper powder well. In addition, the effect | action of the oxide film OM which improves the absorption factor of the near-infrared laser beam L1 with respect to copper powder is based on a well-known knowledge. Therefore, description of the principle etc. which produce an effect is abbreviate | omitted. Further, the absorption rate of the near-infrared laser light L1 into the copper powder varies depending on the thickness of the oxide film OM as shown in the graph of FIG.

  In the graph of FIG. 6, the horizontal axis represents the film thickness (nm) of the oxide film OM formed on the surface of the copper member, and the vertical axis represents the near-infrared laser light L1 applied to the copper member via the formed oxide film OM. It is an experimental data which is the absorptivity (%) of the near-infrared laser beam L1 to the copper member when irradiated. In this experiment, copper powder was not used as the object of irradiation with the near-infrared laser beam L1, but a square member having a side of 10 mm was used. However, an approximate result was obtained when an oxide film OM was formed on the surface of each copper powder. The data of the copper member in FIG.

  As seen from the graph of FIG. 6, the absorption rate of the near-infrared laser beam L1 is alternately a maximum value and a minimum value with respect to a change in the increasing direction of the film thickness in relation to the film thickness of the oxide film OM. It has periodicity that appears. Further, when the thickness of the oxide film OM is 0, the absorption rate is the smallest. Accordingly, the inventor corresponds to the first maximum value a corresponding to the first maximum value a in which the predetermined thickness of the oxide film OM exceeds zero and the absorption rate first appears as a maximum value in relation to the absorption rate having periodicity. It was decided to set it within the range of a maximum film thickness A or less. This ensures that the absorption rate of the copper powder after the oxide film is formed is greater than the absorption rate of the copper powder on which no oxide film is formed.

  In addition, although it is the conditions of said experiment, the used near-infrared laser beam L1 is based on a YAG laser, and is a continuous wave CW laser beam. The oxide film OM was formed in a heating furnace. Further, the thickness of the oxide film OM was measured by the SERA method (continuous electrochemical reduction method). The SERA method is a known film thickness measurement method. Specifically, first, an electrolytic solution is applied to the metal surface, and a reductive reaction is caused by flowing a minute current from the electrode. At this time, since each substance has a specific reduction potential, the film thickness can be calculated by measuring the time required for the reduction. Moreover, the particle size of each copper powder of the metal powder 15 (copper powder) to which the data of the graph of FIG. 6 is applied is in the range of 20 μm to 60 μm, and the average particle size D50 is about 40 μm. The particle size is measured by a known laser diffraction / scattering method. Moreover, the data of FIG. 6 shows an example of the relationship between the absorptance of the near-infrared laser beam L1 and the film thickness of the oxide film OM, and the numerical values are not limited to this.

  The assisting light beam irradiation device 41 shown in FIG. 1 is an apparatus provided in the manufacturing apparatus 100 that emits an assisting light beam having a wavelength different from that of the near-infrared laser light L1 toward the metal powder 15. In the support light beam irradiation device 41, irradiation of the support light beam is controlled by the absorption rate improvement support unit 40. As described above, the support light beam is the short-wavelength laser light L2 having a short wavelength (for example, a wavelength of 0.2 μm to 0.6 μm) shorter than the near-infrared wavelength.

  As described above, the short-wavelength laser light L2 is, for example, copper or aluminum as shown in the relationship between the laser light wavelength (μm) and the laser light absorption rate (%) for each material in FIG. On the other hand, the absorptance is higher than near-infrared wavelength laser light. However, its operating cost is higher than that of near-infrared wavelength laser light. Therefore, in the present invention, the short wavelength laser beam L2 (support light beam) is not used for melting the metal powder 15 that requires high output (modeling process), but mainly in the absorption rate improvement support process. Used for forming the oxide film OM as shown in FIG.

  The assisting light beam irradiation device 41 differs from the modeling light beam irradiation device 30 in the wavelength of the laser light oscillated by the laser oscillator 43. Moreover, the point which does not have a galvano scanner differs with respect to the modeling light beam irradiation apparatus 30. FIG. Thereby, the laser beam irradiated from the laser head 42 is only in a certain direction.

  Further, the assisting light beam irradiation device 41 is arranged with a predetermined angle β ° with respect to the vertical direction so that the laser head 42 does not interfere with the laser head 32 of the modeling light beam irradiation device 30. Further, the assisting light beam irradiation device 41 controls the irradiation position of the laser light when the laser head 42 is moved by an XY robot (not shown). Thereby, the irradiation position of the short wavelength laser beam L2 can move on the XY axis on the surface of the thin film layer 15a of the metal powder 15 in the chamber 10. In the present embodiment, the XY plane is a plane parallel to the horizontal plane.

  Further, the short wavelength laser light L2 can be irradiated with a larger spot diameter as compared with the spot diameter of the near infrared laser light L1. That is, the short wavelength laser beam L2 can be irradiated with a reduced power density by increasing the spot diameter. The irradiation of the short wavelength laser beam L2 is performed within the irradiation range Ar1 shown in FIG. 2, and the irradiation position performed by the control of the XY robot is controlled by the absorptance improvement support unit 40. Other than the above, since it is the same as that of the modeling light beam irradiation device 30, detailed description and drawings are omitted.

  The film thickness estimation unit 50 of the absorption rate improvement support unit 40 estimates the thickness of the oxide film OM formed on the surface of the thin film layer 15a by the absorption rate improvement support process. As shown in FIG. 1, the film thickness estimation unit 50 includes a surface temperature measurement unit 51, an irradiation time measurement unit 52, and an oxide film thickness calculation unit 53.

  The surface temperature measurement unit 51 measures the surface temperature T of the thin film layer 15a during the superimposed irradiation of the short wavelength laser light L2 and the near infrared laser light L1 on the surface of the thin film layer 15a during the oxide film forming process. At this time, the surface temperature T is measured by a non-contact infrared radiation thermometer 39 (see FIG. 1). However, the present invention is not limited to this mode, and the temperature measurement may be performed using any measuring device. The measured surface temperature data of the thin film layer 15 a is transmitted to the oxide film thickness calculator 53.

  The irradiation time measuring unit 52 measures each irradiation time H in which the short wavelength laser beam L2 and the near-infrared laser beam L1 are superimposed and irradiated on the surface of the thin film layer 15a during the oxide film forming process. In this case, the irradiation time H may actually be measured. However, the present invention is not limited to this mode, and preset irradiation time data may be acquired from the control unit 45. Thereafter, the irradiation time data is transmitted to the oxide film thickness calculator 53.

  The oxide film thickness calculation unit 53 calculates and estimates the film thickness of the oxide film OM based on the measured surface temperature T and the measured irradiation time H. The thickness of the oxide film OM is a thickness according to the surface temperature T of the thin film layer 15a that is increased by the superimposed irradiation of the short-wavelength laser light L2 and the near-infrared laser light L1, and the irradiation time H (irradiation duration) of the superimposed irradiation. Is formed. That is, each film thickness of the oxide film OM can be calculated by the surface temperature T and the irradiation time H.

  The process switching determination unit 60 of the absorption rate improvement support unit 40 determines whether or not the film thickness of the oxide film OM calculated by the oxide film thickness calculation unit 53 has reached a predetermined film thickness. Then, when the process switching determination unit 60 determines that the thickness of the oxide film OM has reached a predetermined film thickness, the process to be performed is switched from the absorption rate improvement support process to the modeling process by the modeling unit 70 described later.

  Note that, when there are a plurality of portions where the oxide film OM is formed as in the present embodiment, the process switching determination unit 60 starts the process to be performed after the formation of all the oxide films OM from the absorption rate improvement support process. It switches to the modeling process by the modeling part 70 mentioned later.

  The modeling unit 70 operates the modeling light beam irradiation device 30 by the near-infrared laser light irradiation unit 47 of the control unit 45 after performing the absorption rate improvement support process, and generates near-infrared laser light L1 (modeling light beam). The controller irradiates the oxide film OM having a predetermined thickness formed on the surface of the thin film layer 15a.

  Not limited to this aspect, the modeling unit 70 operates the modeling light beam irradiation device 30 and the support light beam irradiation device 41 by the near-infrared laser beam irradiation unit 47 and the short wavelength laser beam irradiation unit 46 of the control unit 45. The near-infrared laser beam L1 (modeling beam) and the short wavelength laser beam L2 (support beam) may be simultaneously irradiated toward the oxide film OM.

  Thereby, mainly the near-infrared laser beam L1 is favorably absorbed into each copper powder from the surface of each copper powder present on the surface layer of the thin film layer 15a according to the thickness of the oxide film OM. Thus, the modeling part 70 performs the modeling process which heats the thin film layer 15a, fuse | melts the thin film layer 15a, and solidifies after that, and laminate-models a modeling thing.

  Specifically, mainly by irradiation with the near-infrared laser beam L1, the temperature of each surface copper powder in the thin film layer 15a rises above the melting point of copper, and each copper powder melts in a short time. And the heat | fever of the copper powder of the raise thin film layer 15a raises also the temperature of the copper powder of the lower layer which contact | connects each copper powder of the surface layer under the copper powder of the surface layer, and makes it fuse | melt. In this way, the thin film layer 15a is melted in a chain in a short time. Thereafter, by cooling the melted thin film layer 15a, the interface is satisfactorily bonded to the solidified thin film layer 15b already formed below the thin film layer 15a, and the layered modeling is performed.

(1-3. Manufacturing method)
Next, the manufacturing method of a molded article is demonstrated based on the flowchart 1 of FIG. The manufacturing method of a molded article includes a metal powder supply process S10, an absorption rate improvement support process S20, and a modeling process S30. The absorption rate improvement support process S20 includes a pre-heat treatment process S20a, an oxide film formation process S20b, a film thickness calculation process S20c, a film thickness determination process S20d, and a process switching determination process S20e.

  First, the preparation stage will be described. First, the metal powder 15 is put into the powder container 22. Next, the air in the chamber 10 of the manufacturing apparatus 100 is replaced with, for example, He gas by a gas replacement device (not shown). At this time, the air may not be 100% replaced. The air may remain in the chamber 10 by the amount of air containing oxygen that can form the oxide film OM of the nanometer (nm) order on the surface of the thin film layer 15a. The amount of air replacement is obtained in advance by experiments or the like.

  Thereby, when the modeled object is completed, the amount of oxide remaining in the modeled object is minimized, so that the strength of the modeled modeled object is maintained above a certain level. In addition, unintended combustion does not occur when each laser beam is irradiated.

  In the metal powder supply step S10, the metal powder supply control unit 25 of the control unit 45 operates the metal powder supply device 20 to supply the metal powder 15 on the model lifting table 23, and the metal powder 15 is supplied to the irradiation range Ar1. A thin film layer 15a is formed. For this reason, the metal powder supply controller 25 first raises the feed table 24 on which the metal powder 15 is placed, and lowers the shaped article lifting table 23 by one layer of the thin film layer 15a.

  Then, the recoater 26 is moved from right to left in FIG. 1 to supply the metal powder 15 from the powder container 22 to the modeling container 21 and form a thin film layer 15a of powder on the model lifting table 23. To do.

  Next, in the absorptance improvement support process S20, in order to improve the absorptance to the metal powder 15 of the near-infrared laser light L1 (modeling light beam) by the control of the absorptance improvement support unit 40, Then, a predetermined absorption rate improvement support process is performed. At this time, as described above, the absorption rate improvement support process uses the near-infrared laser light L1 (modeling light beam) and the short wavelength laser light L2 (support light beam) to form the oxide film OM on the surface of the thin film layer 15a. Is a process of forming

  Specifically, the pre-heat treatment step S20a (absorption rate improvement support step S20) performs pre-heat treatment for pre-heating by irradiation with the short wavelength laser beam L2. In the pre-heat treatment step S20a, the laser light irradiation control unit 49 included in the absorption rate improvement support unit 40 controls the short wavelength laser light irradiation unit 46, and first activates the support light beam irradiation device 41.

  As a result, as shown in FIG. 8A, the fifth irradiation position P5 on the surface of the thin film layer 15a in the irradiation range Ar1 is irradiated with the short wavelength laser beam L2 (supporting light beam) with the fifth spot diameter φE, and the pre-heat treatment is performed. To implement. The fifth spot diameter φE is a relatively large diameter. For this reason, in the 5th irradiation position P5, the short wavelength laser beam L2 is irradiated with a power density smaller than the power density which can be irradiated originally. And the short wavelength laser beam L2 heats so that the 5th irradiation position P5 may be 600 to 800 degreeC.

  What is necessary is just to monitor the surface temperature T of the 5th irradiation position P5 with the non-contact-type infrared radiation thermometer 39 (refer FIG. 1), for example. And if it confirms that the temperature of the 5th irradiation position P5 will be 600 to 800 degreeC, for example, pre-heat processing will be stopped.

  Next, in the oxide film formation processing step S20b (absorption rate improvement support step S20), the laser beam irradiation control unit 49 controls the short wavelength laser beam irradiation unit 46 and the near-infrared laser beam irradiation unit 47 to support light. The beam irradiation device 41 and the modeling light beam irradiation device 30 are operated simultaneously. As a result, as shown in FIG. 8B, the short-wavelength laser light L2 and the near-infrared laser light L1 are superimposed on the surface of the thin film layer 15a that has been preheated and kept warm.

  At this time, the irradiation position and irradiation spot diameter of the short wavelength laser beam L2 are the same as the irradiation spot diameter at the time of the pre-heat treatment (fifth irradiation position P5, fifth spot diameter φE). Therefore, the short wavelength laser beam L2 may be continuously irradiated from the pre-heat treatment.

  Further, the sixth spot diameter φF (corresponding to the fourth spot diameter φD), which is the spot diameter of the irradiation with the near-infrared laser beam L1, is smaller than the fifth spot diameter φE (corresponding to the third spot diameter φC). Is the diameter. The near-infrared laser beam L1 is superimposed and applied to a predetermined position within the range of the fifth spot diameter φE, which is the irradiation range of the short wavelength laser beam L2.

  At this time, the predetermined position is a position based on slice data (drawing pattern) of a three-dimensional structure to be produced from now on, and is a position where a three-dimensional structure is desired to be formed. Needless to say, the fifth irradiation position P5, which is the irradiation position irradiated with the short-wavelength laser light L2, is also set based on slice data (drawing pattern) of the three-dimensional structure to be manufactured.

  Then, at the position on the surface of the thin film layer 15a where the near-infrared laser beam L1 is irradiated with the short-wavelength laser beam L2, the oxide film OM is formed when the surface temperature T at the irradiation position approaches the melting point of copper. start.

Next, in the film thickness calculation step S20c (absorption rate improvement support step S20), the film thickness estimation unit 50 calculates the film thickness t of the oxide film OM formed on the surface of the thin film layer 15a.
In the film thickness determination step S20d (absorption rate improvement support step S20), it is determined whether or not the film thickness t of the oxide film OM calculated in the film thickness calculation step S20c is within a predetermined film thickness range. Determined by the unit 60.

  The calculated thickness t of the oxide film OM is within the range of a predetermined thickness, which is in the range of B (nm) to A (nm), which is greater than 0 and less than or equal to A (nm). Then, the irradiation of the near-infrared laser beam L1 at the position is stopped, and the process proceeds to the process switching determination step S20e. However, if the film thickness t is not within the range of B (nm) to A (nm), the process moves to the film thickness calculation step S20c, and the film thickness t is within the range of B (nm) to A (nm). Until it enters, S20c and S20d are repeatedly processed.

  B (nm) to A (nm) are film thicknesses corresponding to the absorptances b% to a% in the graph of FIG. Further, the predetermined film thickness range may be set in any range as long as it is in the range of more than 0 and not more than A (nm). At this time, as an example, a predetermined film thickness (B (nm) to A (nm)) corresponds to an absorption rate of 10% (b%) to 60% (a%) as shown in the graph of FIG. It may be 5 nm to 85 nm. However, the set film thickness is merely an example, and the numerical value can be arbitrarily changed. Further, the value of A (nm) is not limited to 85 nm. The oxide film OM is formed on the outermost surface of each copper powder of the metal powder 15 as shown in FIG.

  In the processing switching determination step S20e (absorption rate improvement support step S20), the processing switching determination unit 60 does not form all of the plurality of oxide films OM to be formed in the thin film layer 15a, and the oxide film to be formed. If it is determined that OM still remains, the process returns to the oxide film forming process step S20b, and the irradiation position of the near-infrared laser light L1 is changed within the irradiation range of the short-wavelength laser light L2, thereby forming the next oxide film OM. To do. Such a process is repeated to form a plurality (all locations) of oxide films OM necessary for forming a modeled object within the irradiation range Ar1 (see FIG. 8C).

  However, in the process switching determination step S20e, when the process switching determination unit 60 determines that all the oxide films OM to be formed have been formed, the process is switched from the oxide film forming process to the modeling process, and the modeling process S30 is performed. Moving. As described above, in the present embodiment, all the oxide films OM to be formed are formed in a state where the film thickness has reached a predetermined thickness by superimposing irradiation of the short wavelength laser light L2 and the near infrared laser light L1. When it is determined, the absorption rate improvement support process is switched to the modeling process. In this way, a plurality of oxide films OM necessary for forming the modeled object are formed with the sixth spot diameter φF smaller than the fifth spot diameter φE within the range of the fifth spot diameter φE (see FIG. 8C).

  The film thickness of the oxide film OM calculated in the film thickness calculation step S20c is the film thickness estimation unit 50 (surface temperature measurement unit 51, irradiation time measurement unit 52, and oxide film thickness calculation unit 53 as described above. ) To estimate. Since the operation of the film thickness estimation unit 50 is as described above, detailed description thereof is omitted.

  In modeling process S30 (modeling process), modeling part 70 with which control part 45 is provided operates modeling light beam irradiation device 30, and as shown in Drawing 8D, near infrared laser beam L1 (modeling light beam) is made into a thin film. Irradiate each oxide film OM on the surface of the layer 15a with the sixth spot diameter φF. For this reason, the near-infrared laser light L1 favorably heats the metal powder 15 in which the absorptance of the near-infrared laser light L1 is improved by forming the oxide film OM.

  Then, after melting the metal powder 15 in a short time, the metal powder 15 is solidified to form the thin film layer 15a as the solidified thin film layer 15b and laminate modeling. As shown in FIG. 8E, when the formation of the thin film layer 15a at all oxide film OM formation positions as the solidified thin film layer 15b is completed, the process returns to S10. And it starts again from formation of the next thin film layer 15a by the metal powder supply apparatus 20.

  In the above, in the absorption rate improvement support step S20, a plurality of oxide films OM having a predetermined film thickness are formed by overlapping irradiation with the short wavelength laser light L2 and the near infrared laser light L1, and then the forming step S30 is performed. moved. And in modeling process S30, the near-infrared laser beam L1 was irradiated, the solidified thin film layer 15b was formed, and the modeling thing was laminate-modeled.

  However, it is not limited to this aspect. In the absorptance improvement support step S20, an oxide film OM having a predetermined film thickness is formed by overlapping irradiation with the short wavelength laser beam L2 and the near-infrared laser beam L1, and then a film thickness determination step S20d and a process switching determination step. It moves to modeling process S30 by determination of S20e, may irradiate near infrared laser beam L1, may form the solidified thin film layer 15b, and may laminate-model a modeling thing. In this case, a plurality of solidified thin film layers 15b are formed by reciprocating a plurality of times between the absorption rate improvement support step S20 and the modeling step S30.

(1-4. Modification of First Embodiment)
In the first embodiment, in the modeling step S30, the solidified thin film layer 15b is formed by layered modeling by irradiation with only the near-infrared laser beam L1 (modeling light beam). However, it is not limited to this aspect. As a modification of the first embodiment, in the modeling step S30, the irradiation with the short wavelength laser light L2 in the absorption rate improvement support step S20 is not stopped, and the near infrared laser light L1 is converted into the short wavelength laser as in FIG. 8B. The light L2 may be superimposed and irradiated. Thereby, more energy is consumed than in the first embodiment, but the solidified thin film layer 15b can be formed in a shorter time by the energy of the short wavelength laser beam L2.

(1-5. Modification 1 of First Embodiment)
In the first embodiment, in the pre-heat treatment step S20a (absorption rate improvement support step S20), when the pre-heat treatment is performed on the surface of the thin film layer 15a, only the short wavelength laser beam L2 is irradiated. However, it is not limited to this aspect. As a first modification of the first embodiment, when performing the pre-heat treatment in the pre-heat treatment step S20a, the near-infrared laser light L1 may be superimposed and irradiated in addition to the short wavelength laser light L2, as in FIG. 8B. . In this case, the irradiation range of the near-infrared laser beam L1 is narrower than the irradiation range of the short wavelength laser beam L2, but it can be expected that the pre-heat treatment of the thin film layer 15a is completed earlier than in the first embodiment.

(1-6. Modification 2 of First Embodiment)
Also, in the modified embodiment of the first embodiment, when performing the pre-heat treatment, as shown in FIG. 8B, as in the modified example 1 of the first embodiment, the near-infrared laser beam is added in addition to the short wavelength laser beam L2. L1 may be superimposed and irradiated. This aspect is referred to as a second modification of the first embodiment. Even in this case, it can be expected that the preheating of the thin film layer 15a is completed earlier than the modification of the first embodiment.

<2. Second embodiment>
(2-1. Manufacturing apparatus 200)
Next, a second embodiment will be described. The manufacturing apparatus 200 of the second embodiment shown in FIG. 1 differs from the manufacturing apparatus 100 of the first embodiment in that the absorption rate improvement support process of the absorption rate improvement support unit 40 does not have pre-heat treatment. Further, the manufacturing apparatus 200 is partially different from the manufacturing apparatus 100 of the first embodiment in a process (oxide film forming process) for forming the oxide film OM in the absorption rate improvement support process.

  Specifically, in the manufacturing apparatus 100 according to the first embodiment, in the oxide film formation process, the fifth spot is placed at the fifth irradiation position P5 in the irradiation range Ar1 of the metal powder 15 with the short wavelength laser beam L2 (supporting light beam). At the same time as the irradiation with the diameter φE, the near-infrared laser light L1 (modeling light beam) is superimposed on the short-wavelength laser light L2 (supporting light beam) with the sixth spot diameter φF smaller than the fifth spot diameter φE. Thus, the oxide film OM was formed.

  However, in the manufacturing apparatus 200 of the second embodiment, as shown in FIG. 9A, in the oxide film forming process, the short wavelength laser beam L2 (supporting light beam) is irradiated at the first irradiation position P1 within the irradiation range Ar1 of the metal powder 15. Is irradiated with the first spot diameter φA simultaneously with the near-infrared laser beam L1 (modeling light beam) superimposed on the first irradiation position P1 on the short wavelength laser beam L2 (support light beam) with the first spot diameter φA. Then, the oxide film OM is formed.

  That is, the irradiation spot diameters of the short wavelength laser beam L2 and the near infrared laser beam L1 are the same, which is greatly different from the first embodiment. Then, as shown in FIG. 9B, the modeling unit 70 irradiates the near-infrared laser beam L1 (modeling light beam) to the first irradiation position P1 that is the formation position of the oxide film OM with the first spot diameter φA. Implement (control) processing. The modeling process by the modeling unit 70 is the same as in the first embodiment.

  According to the second embodiment, in the molded article manufacturing apparatus 200, the absorption rate improvement support process is a process of forming the oxide film OM on the surface of the metal powder 15, and the absorption rate improvement support unit 40 has a short wavelength. At the same time as the laser beam L2 (supporting light beam) is irradiated to the first irradiation position P1 in the irradiation range Ar1 of the metal powder 15 with the first spot diameter φA, the near-infrared laser beam L1 (modeling light beam) is irradiated to the first irradiation position. The oxide film OM is formed by irradiating P1 with the first spot diameter φA so as to be superimposed on the short wavelength laser beam L2 (supporting light beam).

  As a result, even if there is no pre-heat treatment, in the absorption rate improvement support process, the output increases due to the superimposed irradiation of the short-wavelength laser light L2 and the near-infrared laser light L1, which are irradiated with the same diameter and have a high power density. Thus, the oxide film OM can be formed, which is efficient.

(2-2. Modification of Second Embodiment)
In said 2nd embodiment, when performing modeling process, it implemented by irradiation of only the near-infrared laser beam L1, similarly to 1st embodiment. However, it is not limited to this aspect. Similar to FIG. 9A, the modeling processing is performed at the first irradiation position P1 in the irradiation range Ar1 of the metal powder 15 similarly to FIG. 9A, similarly to the absorption rate improvement support processing (oxide film formation processing). At the same time as the irradiation with the first spot diameter φA, the near-infrared laser light L1 (modeling light beam) is applied to the first irradiation position P1 with the first spot diameter φA superimposed on the short wavelength laser light L2 (supporting light beam). May be. This increases the cost, but the modeling process can be completed in a short time.

(2-3. Modification 1 of Second Embodiment)
In the second embodiment, the short wavelength laser beam L2 (supporting light beam) is applied to the first irradiation position P1 within the irradiation range Ar1 of the metal powder 15 when the absorption rate improvement supporting process (oxide film forming process) is performed. At the same time as the irradiation with the first spot diameter φA, the near-infrared laser beam L1 (modeling light beam) is applied to the first irradiation position P1 with the first spot diameter φA superimposed on the short wavelength laser beam L2 (supporting light beam). . Moreover, in the modeling part 70, near infrared laser beam L1 (modeling light beam) was irradiated to the 1st irradiation position P1 which is the formation position of the oxide film OM with 1st spot diameter (phi) A, and the modeling process was implemented.

  However, it is not limited to this aspect. As Modification 1 of the second embodiment, the absorptance improvement support unit 40, as shown in FIG. 10, uses a short wavelength laser beam L2 (supporting light beam) as a third irradiation position P3 within the irradiation range Ar1 of the metal powder 15. Is irradiated with the third spot diameter φC, and at the same time, the near infrared laser light L1 (modeling light beam) is superimposed on the short wavelength laser light L2 (support light beam) with the fourth spot diameter φD smaller than the third spot diameter φC. Then, the oxide film OM may be formed by irradiation. That is, the absorptance improvement support unit 40 may irradiate the short-wavelength laser light L2 irradiated over a wide range with the near-infrared laser light L1 in a narrow range superimposed. As a result, irradiation with the short wavelength laser beam L2 contributes to the formation of an oxide film and does not cost much.

(2-4. Modification 2 of Second Embodiment)
As modification 2 of the second embodiment, only the modeling unit 70 may be changed with respect to modification 1 of the second embodiment. Specifically, as shown in FIG. 10, the modeling unit 70 converts the short-wavelength laser light L <b> 2 (supporting light beam) into a metal powder as shown in FIG. 10 in the same manner as the absorption improvement support unit 40 of Modification 1 of the second embodiment. At the same time that the third irradiation position P3 in the irradiation range Ar1 of 15 is irradiated with the third spot diameter φC, the near spot laser beam L1 (modeling light beam) is the fourth spot diameter smaller than the third spot diameter φC. The shaping process may be performed by superimposing and irradiating the short wavelength laser beam L2 (supporting light beam) with φD. That is, the modeling unit 70 may irradiate the short-wavelength laser light L2 irradiated over a wide range with the near-infrared laser light L1 in a narrow range superimposed. As a result, the irradiation with the short wavelength laser light L2 does not cost much while contributing to heating.

<3. Third Embodiment>
(3-1. Manufacturing apparatus 300)
Next, a third embodiment will be described based on FIG. The manufacturing apparatus 300 of the third embodiment is different from the manufacturing apparatus 100 of the first embodiment in the modeling light beam irradiation apparatus 30. Specifically, the modeling light beam irradiation device 30 and the support light beam irradiation device 41 are integrated to form the modeling light and support light beam irradiation device 130. That is, the manufacturing apparatus 300 can switch and irradiate the near-infrared laser light L1 (modeling light beam) and the short-wavelength laser light L2 (support light beam) with one modeling light and support light beam irradiation device 130. It is a configuration. Therefore, it can be said that the modeling light and support light beam irradiation device 130 includes the support light beam irradiation device 41.

  That is, the manufacturing apparatus 300 includes the chamber 10, the metal powder supply device 20, the modeling light and support light beam irradiation device 130, the absorption rate improvement support unit 140 (the film thickness estimation unit 50 and the process switching determination unit 60), A modeling unit 70. The absorption rate improvement support unit 140 and the modeling unit 70 are provided in the control unit 145 corresponding to the control unit 45. Therefore, only a different point is demonstrated with respect to the manufacturing apparatus 100 of 1st embodiment, and description is abbreviate | omitted about the same part. Moreover, the same code | symbol may be attached | subjected and demonstrated to the same structure.

  The modeling light and assisting light beam irradiation device 130 is irradiated with the near-infrared laser beam L1 (modeling light beam) on the surface of the thin film layer 15a of the metal powder 15 in the chamber 10 supplied to the irradiation range Ar1 by the metal powder supply device 20. ) Or short wavelength laser light L2 (supporting light beam). The near-infrared laser beam L1 and the short wavelength laser beam L2 are switched under the control of the laser switching unit 48 provided in the control unit 145. The modeling light and support light beam irradiation device 130 includes a laser oscillator 131 and a laser head 132. The laser oscillator 131 includes an optical fiber 135 that transmits the near-infrared laser light L1 and the short wavelength laser light L2 oscillated from the laser oscillator 131 to the laser head 132.

  As shown in FIG. 11, the laser head 132 is arranged such that the axis is perpendicular to the surface of the thin film layer 15 a of the metal powder 15 in the chamber 10 at a predetermined distance. Since the laser head 132 has the same configuration as the laser head 32, description thereof is omitted. The absorption rate improvement support unit 140 is a control unit that performs the absorption rate improvement support process using the short wavelength laser light L2 (supporting light beam).

(3-2. Manufacturing method)
Next, a manufacturing method for layered modeling of a model using the near infrared laser beam L1 (modeling light beam) will be described based on the flowchart 2 in FIG. The manufacturing method of a molded article includes a metal powder supply step S10, an absorption rate improvement support step S120, and a modeling step S130. Since there is no change about metal powder supply process S10, description is abbreviate | omitted.

  In the absorptance improvement support step S120, the control of the absorptance improvement support unit 140 improves the absorptance of the near-infrared laser light L1 (modeling light beam) to the metal powder 15, so Absorption rate improvement support processing is performed. The absorption rate improvement support process S120 includes an oxide film formation process S120a, a film thickness calculation process S120b, a film thickness determination process 120c, and a process switching determination process S120d.

  In the oxide film formation processing step S120a (absorption rate improvement support step S120), the oxide film OM is formed by irradiation with only the short wavelength laser beam L2 (support light beam) (oxide film formation processing). For this reason, in the oxide film formation processing step S120a, the laser beam irradiation control unit 49 controls the laser switching unit 48 to operate the short wavelength laser beam irradiation unit 46. Thereby, the short wavelength laser light irradiation part 46 operates the modeling light and support light beam irradiation apparatus 130, and irradiates the surface of the thin film layer 15a with the short wavelength laser light L2.

  As shown in FIG. 13A, the short-wavelength laser light L2 (supporting light beam) is irradiated at the second irradiation position P2 on the surface of the thin film layer 15a in the irradiation range Ar1 with the second spot diameter φB to form the oxide film OM. To do. At this time, the second spot diameter φB is a relatively small spot diameter that enables the short wavelength laser beam L2 to form the oxide film OM on the surface of the thin film layer 15a alone. That is, the short wavelength laser beam L2 is a laser beam having a large power density. Then, when the surface temperature T approaches the vicinity of the melting point of copper at the position where the short wavelength laser beam L2 (supporting light beam) is irradiated, the oxide film OM starts to be formed.

In the film thickness calculation step S120b (absorption rate improvement support step S120), the film thickness estimation unit 50 calculates the film thickness t of the oxide film OM formed on the surface of the thin film layer 15a.
In the film thickness determination step 120c (absorption rate improvement support step S120), it is determined whether or not the film thickness t of the oxide film OM calculated in the film thickness calculation step S120b is within a predetermined film thickness range. Determined by the unit 60.

  If the calculated film thickness t of the oxide film OM is within a predetermined film thickness range, for example, within the range of B (nm) to A (nm), the near-infrared laser beam L1 is irradiated at that position. Is stopped, and the process proceeds to the process switching determination step S120d. However, if the film thickness t is not within the range of B (nm) to A (nm), the process moves to the film thickness calculation step S120b, and the film thickness t is within the range of B (nm) to A (nm). Until it enters, S120b and S120c are repeatedly processed.

  In the process switching determination step S120d (absorption rate improvement support process S120), the process switching determination unit 60 does not form all (all locations) of the plurality of oxide films OM to be formed in the thin film layer 15a. If it is determined that the oxide film OM to be left still remains, the process returns to the oxide film formation processing step S120a, the irradiation position of the short wavelength laser light L2 is changed, and the formation process of the next oxide film OM that is not formed is performed. Then, such a process is repeated to form all of the plurality of oxide films OM necessary for forming the modeled object within the irradiation range Ar1 (see FIG. 13B).

  However, when it is determined in the process switching determination step S120d that all the oxide films OM to be formed are formed, the process switching determination unit 60 switches the process from the oxide film formation process to the modeling process, and the modeling process Move to S130. As described above, in the present embodiment, when it is determined that all the oxide films OM to be formed have reached a predetermined thickness by irradiation with the short wavelength laser light L2, the absorption rate is improved. Switch from support processing to modeling processing.

  In the modeling step S130, the modeling unit 70 included in the control unit 145 controls the laser switching unit 48 to operate the modeling light and support light beam irradiation device 130. As a result, the near-infrared laser beam L1 (modeling light beam) is irradiated to the formation position of each oxide film OM on the surface of the thin film layer 15a with the second spot diameter φB as shown by the solid circle in FIG. 13C.

  Therefore, the near-infrared laser beam L1 heats the metal powder 15 whose absorption rate of the near-infrared laser beam L1 is improved by forming the oxide film OM, and melts and solidifies in a short time to solidify the thin film layer 15a. It is formed as a thin film layer 15b, and a modeled object is layered. When the formation of the thin film layer 15a as the solidified thin film layer 15b at all the oxide film OM formation positions indicated by the two-dot chain line circle in FIG. 13C is completed, the process returns to S10. And it starts again from formation of the next thin film layer 15a by the metal powder supply apparatus 20.

  As described above, in the third embodiment, the near-infrared laser beam L1 (modeling light beam) and the short wavelength laser beam L2 (supporting light beam) are simply provided with one modeling light and supporting light beam irradiation device 130. Since it can be implemented, it can be manufactured at low cost.

<4. Fourth Embodiment>
(4-1. Manufacturing device 400)
Note that the present invention also includes a manufacturing apparatus 400 of the type disclosed in Japanese Patent Application Laid-Open No. 2007-216235 having a configuration different from the manufacturing apparatuses 100 to 300 of the first to third embodiments as the fourth embodiment. Applicable (see FIG. 14). The manufacturing apparatus 400 differs from the manufacturing apparatuses 100 to 300 of the first to third embodiments, the metal powder supply apparatus 20, the modeling light beam irradiation apparatus 30, and the modeling light and support light beam irradiation apparatus 130. Among these, the aspect of the metal powder supply device 20 is particularly different.

  The manufacturing apparatus 400 switches the near-infrared laser beam L1 (modeling light beam) and the short wavelength laser beam L2 (support light beam) while switching one modeling light and the support light beam irradiation device 230 under the control of the laser switching unit 48. Irradiate. Therefore, it can be said that the manufacturing apparatus 400 includes the support light beam irradiation device 41 as in the third embodiment.

  In addition, the manufacturing apparatus 400 integrally includes a metal powder supply device 220 corresponding to the metal powder supply device 20 on the outer peripheral side of the laser head 232 that emits laser light. Further, in the manufacturing apparatus 400, the metal powder supply device 220 and the laser head 232 are disposed in the chamber 210. Since this type of manufacturing apparatus is well known, detailed description thereof is omitted.

  Thereby, the manufacturing apparatus 400 ejects the metal powder 15 from the outer periphery of the laser head 232 into the irradiation range Ar1 by the metal powder supply apparatus 220 and then irradiates the modeling light and the support light beam irradiation apparatus 230 with the short wavelength laser light L2. Oxide film formation processing (absorption rate improvement support processing) is performed by irradiation with (supporting light beam) to form an oxide film OM (not shown in FIG. 14) on the surface of the thin film layer 15a. After the formation of the oxide film OM, the laser switching unit 48 of the control unit 145 changes the laser irradiation of the modeling light and the support light beam irradiation device 230 from the short wavelength laser light L2 to the near infrared laser light L1 (modeling light beam). Switch.

  Thereby, the formation position of the oxide film OM is irradiated from the modeling light and assisting light beam irradiation device 230 to the formation position of the oxide film OM, and modeling processing is performed to form a three-dimensional modeled object. The absorption rate improvement support process and the modeling process are the same as the absorption rate improvement support process S120 and the modeling process S130 of the second embodiment. Thereby, also by the manufacturing apparatus 400, the same three-dimensional modeled object as the modeled object manufactured with the manufacturing apparatus 300 of 3rd embodiment is formed.

<5. Fifth embodiment>
(5-1. Manufacturing apparatus 500)
Next, a fifth embodiment will be described with reference to FIG. The manufacturing apparatus 500 according to the fifth embodiment illustrated in FIG. 15 does not include the assisting light beam irradiation apparatus 41 as compared with the manufacturing apparatus 100 according to the first embodiment. That is, the manufacturing apparatus 500 is an apparatus in which only the near-infrared laser beam L1 (modeling light beam) is irradiated by the modeling light beam irradiation apparatus 30. In the following, only different points will be mainly described with respect to the manufacturing apparatus 100 of the first embodiment, and description of similar parts will be omitted. Moreover, the same code | symbol may be attached | subjected and demonstrated to the same structure.

  The manufacturing apparatus 500 includes a chamber 10, a metal powder supply device 20, a modeling light beam irradiation device 30, a black film forming device 250, and a control unit 245 corresponding to the control unit 45 of the first embodiment. The control unit 245 includes a metal powder supply control unit 25, an absorptance improvement support unit 240, a near-infrared laser light irradiation unit 47, and a modeling unit 70.

  The absorption rate improvement support unit 240 performs a predetermined absorption rate improvement support process on the surface of the metal powder 15 supplied to the irradiation range Ar1. Here, the predetermined absorption rate improvement support process is a process of forming a black film BM by attaching a black material to be described later to the surface of the metal powder 15 after the metal powder 15 is supplied to the irradiation range Ar1.

  The black film forming apparatus 250 is provided in the chamber 10. The black film forming apparatus 250 is controlled by the absorption rate improvement support unit 240 included in the control unit 245. The black film forming apparatus 250 applies carbon black, which is an example of a black material, to the surface of the thin film layer 15a of the metal powder 15 after being supplied to the irradiation range Ar1 by the metal powder supply apparatus 20 as a predetermined absorption rate improvement support process. CB is jetted to adhere.

  The black film forming apparatus 250 has any configuration as long as carbon black CB (black material) stored in a storage container (not shown) can be sprayed and sprayed on the entire surface of the thin film layer 15a. It may be formed. Carbon black CB is a fine particle of carbon produced by quality control industrially, and is a known material used in many fields such as ink and tires. For further detailed explanation, Omitted. The carbon black CB is thinly attached to the surface of the thin film layer 15a of the metal powder 15 (copper powder) supplied to the irradiation range Ar1 to form a black film BM.

  In the present embodiment, the black material is a material formed in black as the name suggests, and is a material having a high absorptance of the near-infrared laser beam L1 (modeling light beam). Examples of the black material include graphite, charcoal, black paint (black ink) and the like in addition to carbon black CB. In the black material, the definition of black is not strict and may be any color that is normally judged as black, such as the above-described graphite, charcoal, and black paint (black ink).

  The modeling unit 70 operates the modeling light beam irradiation device 30 by the near-infrared laser beam irradiation unit 47 after performing the absorption rate improvement support process (formation of the black film BM), and generates the near-infrared laser beam L1 (modeling light). Beam) is irradiated to a predetermined position set on the surface of the thin film layer 15a. At this time, the predetermined position is a position based on slice data (drawing pattern) of a three-dimensional structure to be produced. Thus, the modeling part 70 performs the modeling process which heats the surface of the thin film layer 15a on which the black film BM is formed, melts the thin film layer 15a, and solidifies it later to laminate the modeled object.

(5-2. Manufacturing method)
Next, the manufacturing method of the molded object in 5th embodiment is demonstrated based on the flowchart 3 of FIG. The manufacturing method of a molded article includes a metal powder supply step S10, an absorption rate improvement support step S220, a modeling step S230, and a modeling end confirmation step S240. In addition, metal powder supply process S10 is the same as that of the flowchart 1. In the following, differences from the flowchart 1 of the first embodiment will be mainly described.

  In the absorption rate improvement support step S220, the black film CB is applied to the entire surface of the thin film layer 15a of the metal powder 15 after being supplied to the irradiation range Ar1 by the control of the absorption rate improvement support unit 240. The black film BM is formed by spraying and adhering. The thickness of the black film BM may be about several μm to several tens of μm. However, it is not limited to this thickness.

  The black coating BM efficiently absorbs the near-infrared laser light L1 and quickly raises the temperature. In addition, the black coating BM rapidly raises the temperature of the attached metal powder 15 by heat conduction and keeps the temperature of the metal powder 15 as the temperature rises, thereby assisting the temperature rise of the metal powder 15. Thereby, it can be said that the absorptance of the near-infrared laser beam L1 with respect to the metal powder 15 (copper powder) is improved by forming the black film BM as in the above-described embodiment in which the oxide film OM is formed.

  In the modeling step S230 (modeling process), the modeling unit 70 of the control unit 245 operates the modeling light beam irradiation device 30 to irradiate a predetermined irradiation position on the surface of the thin film layer 15a with a predetermined irradiation diameter ( (Not shown).

  When the near-infrared laser beam L1 (modeling light beam) is applied to the black coating BM formed on the surface of the thin film layer 15a, as described above, the black coating BM rapidly rises in temperature. Along with this, the black coating BM quickly keeps the temperature of the metal powder 15 in contact with the heat by conducting heat.

  Thereafter, when the heated thin film layer 15a exceeds the melting point (for example, 1060 ° C.), the thin film layer 15a is melted and joined to the lower solidified thin film layer 15b to be layered. At this time, when the metal powder 15 is melted, the black film BM (carbon black CB) is already vaporized and is not mixed into the melted metal powder 15.

  Here, the vaporization of the black film BM (carbon black CB) will be briefly described. In the above, the vaporization temperature of carbon black CB (black film BM) is higher than the melting point of copper powder (metal powder 15). However, carbon black (black film BM) is thinly attached to the surface of the thin film layer 15a. For this reason, the volume of the black film BM, that is, the heat capacity in the portion irradiated with the near-infrared laser beam L1 is small. Therefore, the black coating BM can reach the vaporization temperature before the metal powder 15 reaches the melting point by irradiation of the black coating BM with the near infrared laser light L1. Thus, in the modeling process, the black film BM (carbon black CB) is vaporized before the metal powder 15 is melted and is not mixed into the metal powder 15.

  In such a process, the metal powder 15 is melted in a short time, and then solidified to form the thin film layer 15a as the solidified thin film layer 15b to be layered. When the near-infrared laser beam L1 has been irradiated to the predetermined irradiation positions of all slice data on the surface of one thin film layer 15a, the process proceeds to the modeling completion confirmation step S240.

  In the modeling end confirmation step S240, it is confirmed whether or not the layered modeling has been performed on all of the plurality of thin film layers 15a that are set in advance as a layered model. If it is determined in the modeling end confirmation step S240 that there is a thin film layer 15a that has not yet been layered, the process returns to the metal powder supply step S10. And it starts again from formation of the next thin film layer 15a by the metal powder supply apparatus 20.

  Thereafter, after the thin film layer 15 a is supplied to the irradiation range Ar <b> 1 by the metal powder supply device 20, the black film BM is formed on the surface of the metal powder 15 by the control of the absorption rate improvement support unit 240 each time. By repeating such a process, a three-dimensional structure can be formed in a shorter time than before. In addition, when it is determined in the modeling end confirmation step S240 that all of the planned layered modeling of the plurality of thin film layers 15a has been completed, the program is terminated.

(5-3. Others)
In the fifth embodiment, the black film BM is formed on the entire surface of the thin film layer 15a of the metal powder 15 after being supplied to the irradiation range Ar1 in the absorption improvement support step S220. However, it is not limited to this aspect. The range of the black coating BM formed on the surface of the thin film layer 15a is a predetermined range in which the modeling unit 70 irradiates the surface of the thin film layer 15a of the metal powder 15 with the near-infrared laser beam L1 (modeling light beam) in order to perform the modeling process. Only the range corresponding to the irradiation position may be used. As a result, the black coating BM is not formed on the portion that is not irradiated with the near-infrared laser beam L1 (modeling light beam), so that the amount of carbon black CB used can be suppressed and the cost can be reduced.

  In the fifth embodiment, after the thin film layer 15a is completely supplied to the irradiation range Ar1, the carbon black CB is sprayed on the surface of the thin film layer 15a to form the black film BM. However, it is not limited to this aspect. The black coating BM may be formed while following at a timing slightly delayed from the timing at which the thin film layer 15a of the metal powder 15 is supplied to the irradiation range Ar1. This also provides the same effect.

  Moreover, in the said 5th embodiment, carbon black CB was sprayed on the surface of the thin film layer 15a of the metal powder 15 after having been supplied to irradiation range Ar1, and the black film BM was formed. However, it is not limited to this mode. As another modification, the absorption rate improvement support unit 240 may manufacture the absorption rate improvement support process as follows.

  Specifically, carbon black CB is mixed and stirred in the raw material (corresponding to the metal powder aggregate) of the metal powder 15 before being supplied to the irradiation range Ar1. Thereby, carbon black CB is made to adhere to the surface of each metal powder of a raw material, and the raw material (metal powder aggregate | assembly) with the black membrane | film | coat BM is manufactured.

  In this case, a predetermined amount of carbon black CB may be put into a container in which the raw material of the metal powder 15 is stored, and stirred by hand or machine (not shown). Thereafter, when each metal powder of the raw material with carbon black CB adhering to the entire outer surface is supplied to the irradiation range Ar1 by the metal powder supply device 20, the surface of the metal powder 15 supplied to the irradiation range Ar1 is surely In this state, carbon black CB is attached to the surface, that is, a black film BM is formed. Thereby, the effect similar to the said 5th embodiment is acquired.

(4. Effects of the above embodiment)
As is clear from the above, according to the first to fifth embodiments, the manufacturing apparatus 100 to 500 of the modeled object sinters the metal powder 15 by irradiation of the near infrared laser beam L1 (modeling light beam). It is the manufacturing apparatus 100-500 of the molded article which is solidified by melting and layered. Manufacturing apparatuses 100 to 500 are provided in chambers 10 and 210 capable of blocking outside air and inside air, and inside chambers 10 and 210, and irradiation range of metal powder 15 with near-infrared laser light L <b> 1 (modeling light beam). Irradiate the surface of the metal powder 15 (thin film layer 15a) in the chambers 10 and 210 supplied to the irradiation range Ar1 with the near-infrared laser beam L1 (modeling light beam) supplied to the Ar1 metal powder supply devices 20 and 220. Of the modeling light beam irradiation apparatus 30 (modeling light and support light beam irradiation apparatuses 130 and 230) and the irradiated near-infrared laser light L1 (modeling light beam) to the metal powder 15 (thin film layer 15a) In order to improve the absorption rate improvement support units 40, 140, and 240 that perform a predetermined absorption rate improvement support process on the metal powder 15 (thin film layer 15a), and after the implementation of the absorption rate improvement support process The near-infrared laser beam L1 (modeling light beam) is irradiated onto the metal powder 15 (thin film layer 15a) supplied to the irradiation range Ar1, and the metal powder 15 (thin film layer 15a) is heated and solidified by sintering or melting. And a modeling unit 70 that performs modeling processing for layered modeling.

  Thus, the manufacturing apparatus 100-500 of the modeled object has the absorptance of the near-infrared laser beam L1 (modeling light beam) with respect to the metal powder 15 (thin film layer 15a) by the absorption rate improvement support units 40, 140, and 240. After performing the absorption improvement improvement process to raise, the near-infrared laser beam L1 (modeling light beam) is irradiated to the metal powder 15 (thin film layer 15a). For this reason, the near-infrared laser beam L1 is favorably absorbed by the metal powder 15 (thin film layer 15a). Accordingly, since the metal powder 15 (thin film layer 15a) is heated well and solidified by sintering or melting by the short-time irradiation of the near-infrared laser beam L1, the time for layered modeling can be shortened and the cost can be reduced. Can be produced.

  Moreover, according to the said embodiment, the manufacturing apparatuses 100-300 of the molded article which concern on 1st-3rd embodiment are short wavelength laser beam L2 (support) of the wavelength different from near-infrared laser beam L1 (modeling light beam). A support light beam irradiation device 41 that irradiates the metal powder 15 (thin film layer 15a) with a light beam is provided (or can be regarded as provided). And the absorptance improvement support part 40,140 implements an absorptance improvement support process using the short wavelength laser beam L2 (support light beam) at least, and the modeling part 70 at least uses the near infrared laser beam L1 (modeling light). A modeling process is performed using a beam.

  The short wavelength laser beam L2 (supporting light beam) has a high operating cost, but has a good absorption rate to the metal powder 15. For this reason, the pre-heat treatment and the oxide film formation process in the absorption rate improvement support process that does not require a large output may be performed at a relatively low cost by irradiating with a low output. Since the absorption processing is performed by the near-infrared laser beam L1 (modeling light beam) with a low operation cost in the state where the absorption rate of the metal powder 15 is improved by the absorption rate improvement support processing, this can also be manufactured at a low cost. In this way, by making use of the characteristics of the laser beams L1 and L2, both the absorption rate improvement support processing and the modeling processing are inexpensive.

  Further, according to the modification of the first embodiment, the modification 2 of the first embodiment, the modification of the second embodiment, and the modification 2, the modeling unit 70 includes the near-infrared laser beam L1 (modeling light). The modeling process is performed using both the beam) and the short-wavelength laser light L2 (supporting light beam). Thereby, a modeling process can be implemented in a short time.

  Further, according to the first and second embodiments, the absorptance improvement support units 40 and 140 use both the near-infrared laser light L1 (modeling light beam) and the short-wavelength laser light L2 (support light beam). And implement absorption rate improvement support processing. Thereby, the absorption rate improvement support process can be implemented in a short time.

  Further, according to the first embodiment, the absorption rate improvement support process is a process of forming the oxide film OM on the surface of the metal powder 15 (thin film layer 15a). And the absorptance improvement assistance part 40 irradiates the 3rd irradiation position P3 in the irradiation range Ar1 of the metal powder 15 (thin film layer 15a) with the 3rd spot diameter (phi) C simultaneously with the short wavelength laser beam L2 (support light beam). The oxide film OM is formed by irradiating the near-infrared laser beam L1 (modeling light beam) on the support light beam with a fourth spot diameter φD smaller than the third spot diameter φC. Then, the modeling unit 70 performs modeling processing by irradiating at least the near-infrared laser beam L1 (modeling light beam) to the formation position of the oxide film OM with the fourth spot diameter φD.

  As described above, at the time of forming the oxide film OM, the short wavelength laser light L2 (supporting light beam) that irradiates a wide range (third spot diameter φC) and a narrower range (fourth spot diameter φD) than the short wavelength laser light L2. Therefore, by superimposing the near-infrared laser beam L1 (modeling light beam) on the short-wavelength laser beam L2, a high output is obtained in the superimposed portion. For this reason, the oxide film OM can be formed in a short time.

  Further, according to the first embodiment, the absorption rate improvement support process preheats the metal powder 15 (thin film layer 15a) and forms an oxide film OM on the surface of the metal powder 15 (thin film layer 15a) after the preheating. It is processing to do. Then, the absorptance improvement support unit 40 transmits at least the short-wavelength laser light L1 (supporting light beam) at the fifth irradiation position P5 in the irradiation range Ar1 of the metal powder 15 with the fifth spot diameter φE ( Pre-heat treatment is performed before irradiation with the modeling light beam. Thereafter, the short-wavelength laser light L2 (supporting light beam) is irradiated to the fifth irradiation position P5 in the irradiation range Ar1 of the metal powder 15 with the fifth spot diameter φE, and at the same time, the near-infrared laser light L1 (modeling light beam) is irradiated. The oxide film OM is formed by superimposing and irradiating the short-wavelength laser light L2 (supporting light beam) with a sixth spot diameter φF smaller than the fifth spot diameter φE. The modeling unit 70 performs modeling processing by irradiating at least the near-infrared laser beam L1 (modeling light beam) to the formation position of the oxide film OM with the sixth spot diameter φF.

  As described above, the absorption rate improvement support process preheats the metal powder 15 (thin film layer 15a), and forms an oxide film OM on the surface of the metal powder 15 (thin film layer 15a) after preheating. Thereby, the time for forming the oxide film OM can be shortened. Further, when the oxide film OM is formed, the short wavelength laser light L2 that irradiates a wide range (fifth spot diameter φE) and the short wavelength laser light L2 (sixth spot diameter φF) is narrower than the short wavelength laser light L2 (sixth spot diameter φF). By superimposing the near-infrared laser beam L1 (modeling light beam) on the assisting light beam), high output is obtained in the superimposed portion. For this reason, the oxide film OM can be formed in a short time.

  Further, according to the first embodiment and the modification of the first embodiment, the absorptance improvement support unit 40 does not use the near-infrared laser light L1 (modeling light beam), but uses the short wavelength laser light L2 (support). Pre-heat treatment is performed using a light beam. As described above, by not using the near infrared laser beam L1 having a low absorption rate to the metal powder 15 for the preheating, the time for the preheat treatment does not change so much but can be implemented at low cost.

  Further, according to the first to fourth embodiments, the absorptance of the near-infrared laser beam L1 (modeling light beam) with respect to the metal powder 15 is increased in the thickness direction in relation to the thickness of the oxide film OM. It has a periodicity in which a maximum value and a minimum value appear alternately with respect to the change to, and has a characteristic that becomes the smallest when the thickness of the oxide film OM is zero. In the absorptance improvement support units 40 and 140, the predetermined film thickness of the oxide film OM formed to exceed zero is greater than zero in relation to the absorption coefficient having periodicity. First, the absorptance is set within the range of the first maximum film thickness A or less corresponding to the first maximum value a that appears as the maximum value. Thus, the absorptance of the near-infrared laser light L1 is reliably improved as compared with the case where the near-infrared laser light L1 (modeling light beam) is absorbed by the metal powder without forming the oxide film OM.

  Further, according to the first to fourth embodiments, the absorption rate improvement support units 40 and 140 have the film thickness of the oxide film OM formed on the surface of the metal powder 15 (thin film layer 15a) by the absorption rate improvement support process. The film thickness estimation unit 50 for estimating the film thickness, and whether or not the estimated film thickness of the oxide film OM has reached a predetermined film thickness are determined. A process switching determination unit 60 that switches from the process to the modeling process by the modeling unit 70.

  In addition, the film thickness estimation unit 50 is superposed on the surface temperature measurement unit 51 that measures the surface temperature T of the thin film layer 15a of the metal powder 15 on which the oxide film OM is formed, or a short wavelength laser beam L2 (supporting light beam). The irradiation time H during which the short-wavelength laser light L2 (supporting light beam) and the near-infrared laser light L1 (modeling light beam) are irradiated on the surface of the thin film layer 15a of the metal powder 15 to form the oxide film OM is measured. And an oxide film thickness calculator 53 that calculates an estimated film thickness of the oxide film OM based on the measured surface temperature T and the measured irradiation time H. Thereby, the film thickness of the oxide film OM can be estimated with high accuracy, and a desired effect of improving the absorption rate can be obtained satisfactorily.

  Further, according to the first to fourth embodiments, the modeling light beam is a near-infrared wavelength laser beam (near-infrared laser beam L1), and the support light beam has a shorter wavelength than the near-infrared wavelength. This is a short wavelength laser beam (short wavelength laser beam L2). As described above, for the absorptivity improvement support process that does not require the thin film layer 15a of the metal powder 15 to be raised to a high temperature, the short wavelength laser light L2 having a short wavelength and a high absorptivity is mainly used. Since the near-infrared laser beam L1 having a low operation cost is used for the modeling process that uses and raises the thin film layer 15a of the metal powder 15 to a high temperature, it can be performed at a low cost.

  Moreover, according to said 1st-5th embodiment, the metal powder 15 is a copper powder. Thereby, in the market, the three-dimensional structure by metal AM can be manufactured with copper powder with high needs.

  Further, according to the fifth embodiment, the absorption rate improvement support process is a process of forming a black film BM by attaching a black material to the surface of the metal powder 15 supplied to the irradiation range Ar1 by the metal powder supply device 20. It is. The absorption rate improvement support unit 240 is supplied to the irradiation range Ar1 by the absorption rate improvement support process before the metal powder 15 is supplied to the irradiation range Ar1 or after the metal powder 15 is supplied to the irradiation range Ar1. A black film BM is formed on the surface of the metal powder 15. Thereby, since the irradiation time of the modeling light beam can be shortened, the absorption rate improvement support process can be performed in a short time, and the cost can be reduced.

  Moreover, according to the said 5th embodiment, the modeling part 70 irradiates the near infrared laser beam L1 (modeling light beam) to the surface of the metal powder 15, and heats the metal powder 15 after implementation of an absorption rate improvement assistance process. However, when solidified by sintering or melting, the black coating BM does not remain in the solidified and layered modeled object. Thereby, the intensity | strength of a molded article becomes high and the quality as a product improves.

  Further, according to the fifth embodiment, the absorption rate improvement support unit 240 is provided inside the chamber 10, and after the metal powder 15 is supplied to the irradiation range Ar1, the black coating BM is formed on the surface of the metal powder 15. A black film forming apparatus 250 is formed. As described above, since the black coating BM is formed after the metal powder 15 is supplied to the irradiation range Ar1, it is possible to avoid attaching an excessive black coating BM to the surface other than the surface of the thin film layer 15a of the metal powder 15, and waste. Less.

  Further, according to the fifth embodiment, the range in which the absorption rate improvement support unit 240 forms the black film BM on the surface of the metal powder 15 is determined by the modeling unit 70 after the absorption rate improvement support process is performed. In order to perform the process, the surface corresponds to a predetermined irradiation position where the surface of the metal powder 15 is irradiated with the near-infrared laser beam L1 (modeling light beam). In this way, since the black coating BM does not have to adhere to the entire surface of the thin film layer 15a in the irradiation range Ar1 of the metal powder 15, the waste is further reduced.

  In addition, according to the fifth embodiment, the black coating BM is formed on the surface of the metal powder 15 by the absorption rate improvement support unit 240 every time after the metal powder 15 is supplied to the irradiation range Ar1 by the metal powder supply device 20. Is done. Thereby, after the metal powder 15 is supplied to the irradiation range Ar1, it is possible to laminate and model each time in a short time, so that a three-dimensional structure that is a finished product can be manufactured in a short time.

  In addition, according to the modification of the fifth embodiment, the absorption rate improvement support unit 240 uses black material (carbon black CB) as a raw material for the metal powder 15 before the metal powder 15 is supplied to the irradiation range Ar1. A black powder BM is formed by mixing in a certain metal powder aggregate and stirring to adhere to the surface of the metal powder. Also by this, the same effect as the fifth embodiment can be obtained.

  Moreover, according to said 1st-5th embodiment, by the irradiation of near-infrared laser beam L1 (modeling light beam), the thin film layer 15a of the metal powder 15 is solidified by sintering or melting, and the modeled object is layered and modeled. The manufacturing method includes a metal powder supply step S10 for supplying the thin film layer 15a of the metal powder 15 to the irradiation range Ar1 of the near-infrared laser beam L1 (modeling light beam), and the irradiated near-infrared laser beam L1 (modeling light beam). In order to improve the absorption rate of the metal powder 15 into the metal powder 15, absorption rate improvement support steps S20, S120, S220 for performing a predetermined absorption rate improvement support process on the thin film layer 15a of the metal powder 15, and an absorption rate improvement support process After the above, the near-infrared laser beam L1 (modeling light beam) is irradiated to the thin film layer 15a of the metal powder 15 supplied to the irradiation range Ar1, and the metal powder 15 (thin film layer 15a) is heated to sinter or melt. Comprises a shaping step S30, S130 to perform the shaping process of the laminate molding solidifying, the by. Thereby, the low-cost three-dimensional structure similar to the three-dimensional structure manufactured by the manufacturing apparatuses 100 to 500 can be manufactured.

  Further, according to the fifth embodiment, the absorption rate improvement support step S220 is performed before the metal powder 15 is supplied to the irradiation range Ar1 or after the metal powder 15 is supplied to the irradiation range Ar1. By the improvement support process, the black coating BM is formed on the surface of the metal powder 15 supplied to the irradiation range Ar1. As described above, the near-infrared laser beam L1 (modeling light beam) can be absorbed with a high absorption rate only by forming the black coating BM, and the cost can be reduced.

(5. Other)
In the first to fourth embodiments, in the absorption rate improvement support process by the absorption rate improvement support units 40 and 140, an oxide film OM having a predetermined thickness is formed on the surface of the thin film layer 15a of the metal powder 15. And the absorptance of near-infrared laser beam L1 (modeling light beam) was improved. However, it is not limited to this aspect. In the absorptance improvement support process, irregularities may be formed on the surface of each copper powder of the metal powder 15, thereby improving the absorptance of the near-infrared laser light L1 (modeling light beam). In this case, the contents of implementation of the absorption rate improvement support steps S20 and S120 are different from those of the first to fourth embodiments, but for other steps (metal powder supply step S10, modeling steps S30 and S130), What is necessary is just to implement similarly.

  It is based on well-known knowledge that the absorptance of the near-infrared laser beam L1 (modeling light beam) is improved by forming irregularities on the surface of each copper powder, and detailed description thereof is omitted. In addition, in order to form an unevenness | corrugation on each copper powder surface, when producing copper powder by the well-known atomizing method, it can implement | achieve by employ | adopting conditions different from the formation conditions for making copper powder spherical. This also provides a reasonable effect.

  In the first to fourth embodiments, the short-wavelength laser light L2 (supporting light beam) or the short-wavelength laser light L2 is applied to the surface of the thin film layer 15a of the metal powder 15 by the absorption enhancement support steps S20 and S120. And the oxide film OM was formed by irradiating the near-infrared laser beam L1 (modeling light beam). However, the present invention is not limited thereto, and the oxide film OM may be formed in advance in a heating furnace. Thereby, although the efficiency which forms the oxide film OM falls, when only modeling process S30, S130 is seen, the effect similar to the said embodiment is acquired.

  In the first to fifth embodiments, the metal powder 15 is copper powder. However, the metal powder is not limited to copper powder, but may be a low absorption material such as aluminum powder. However, in the first to fourth embodiments, when a low absorptivity material such as aluminum is applied as the metal powder, the laser light absorptance-oxide film thickness characteristics are different for each metal. In this case, a predetermined film thickness may be newly set after grasping the absorption rate-oxide film thickness characteristic corresponding to each metal. The low absorptivity material is as described above, and refers to a metal material having an absorptance of near-infrared laser light L1 of 30% or less.

  In the first to fourth embodiments, the film thickness estimation unit 50 forms the oxide film OM on the surface of the thin film layer 15a of the metal powder 15 in the absorption rate improvement support steps S20 and S120. The film thickness of the oxide film OM was calculated. Until the oxide film OM having a predetermined thickness is formed, the short wavelength laser beam L2 (supporting light beam) or the short wavelength laser beam L2 and the near infrared laser beam L1 (modeling light beam) to be irradiated are irradiated. The output was constant. However, it is not limited to this aspect. If the film thickness of the oxide film OM calculated by the film thickness estimation unit 50 is smaller than the desired film thickness, the laser beam irradiation output may be raised thereafter. That is, feedback control may be performed according to the calculated thickness of the oxide film OM. Thereby, a molded article can be manufactured in a shorter time.

  In the first to fourth embodiments, the set value of the film thickness of the oxide film OM formed by the absorption rate improvement support process of the absorption rate improvement support units 40 and 140 is related to the absorption rate having periodicity. The first maximum film thickness A corresponding to the first maximum value a that exceeds zero and the absorption rate first appears as a maximum value. However, it is not limited to this aspect. The thickness of the oxide film OM to be set may be set to a thickness exceeding the first maximum thickness A.

  That is, in the film thickness between the first maximum film thickness A corresponding to the first maximum value a and the first minimum film thickness AA corresponding to the first minimum value aa, the absorption rate is in the range of b% to a%. The film thickness of the oxide film may be set so that Further, the thickness of the oxide film may be set so that the absorptance falls within the range of b% to a% depending on the thickness of the larger oxide film.

  In the first to fourth embodiments, the irradiation spot shapes of the short-wavelength laser light L2 and the near-infrared laser light L1 (modeling light beam) are described as circular. However, it is not limited to this mode. If possible, the shape of the irradiation spot of each laser beam L1, L2 may be rectangular. Also by this, the same effect as the above embodiment can be obtained.

  In the fifth embodiment, the near-infrared laser beam L1 is applied as the modeling light beam. However, the short wavelength laser beam L2 may be applied as the modeling light beam. Thereby, since the manufacturing time of a three-dimensional structure can be further shortened, even if it is expensive short wavelength laser beam L2, the effect corresponding to cost reduction can be anticipated.

  10, 210: chamber, 15: metal powder, 15a: thin film layer, 20, 220: metal powder supply device, 30: modeling light beam irradiation device, 39: infrared radiation thermometer, 40, 140, 240: support for improving absorption rate Part: 41: assisting light beam irradiation device, 45, 145, 245: control part, 50: film thickness estimation part, 51: surface temperature measurement part, 52: irradiation time measurement part, 53: oxide film thickness calculation part, 60: Process switching determination unit, 70: modeling unit, 100, 200, 300, 400, 500: manufacturing apparatus, 130, 230: modeling light and supporting light beam irradiation apparatus, 250: black film forming apparatus, Ar1: irradiation range, BM: Black film, H: Irradiation time, L1: Near-infrared laser beam (modeling light beam), L2: Short wavelength laser beam (supporting light beam), OM: Oxide film, P1: First irradiation P2, second irradiation position, P3: third irradiation position, P5: fifth irradiation position, S10: metal powder supply process, S20, S120, S220: absorption rate improvement support process, S30, S130: modeling process, T : Surface temperature, φA: first spot diameter, φB: second spot diameter, φC: third spot diameter, φD: fourth spot diameter, φE: fifth spot diameter.

Claims (24)

It is a manufacturing apparatus of a modeled object that is solidified by sintering or melting a metal powder by irradiation of a modeling light beam,
A chamber capable of blocking outside air and inside air;
A metal powder supply device that is provided inside the chamber and supplies the metal powder to an irradiation range of the modeling light beam;
A modeling light beam irradiation device for irradiating the modeling light beam to the metal powder in the chamber supplied to the irradiation range;
In order to improve the absorption rate of the shaped light beam to be irradiated into the metal powder, an absorption rate improvement support unit that performs a predetermined absorption rate improvement support process on the metal powder;
After the implementation of the absorptivity improvement support process, the modeling light beam is irradiated onto the metal powder supplied to the irradiation range, the metal powder is heated, and solidified by the sintering or melting to perform the layered modeling. A modeling part to perform,
The manufacturing apparatus of a molded article provided with. The manufacturing apparatus of the model includes a support light beam irradiation device that irradiates the metal powder with a support light beam having a wavelength different from that of the modeling light beam,
The absorption rate improvement support unit performs the absorption rate improvement support process using at least the support light beam,
The said modeling part is a manufacturing apparatus of the molded article of Claim 1 which implements the said modeling process using the said modeling light beam at least.   The said modeling part is a manufacturing apparatus of the molded article of Claim 2 which implements the said modeling process using the said modeling light beam and the said support light beam.   The said absorption rate improvement assistance part is a manufacturing apparatus of the molded article of Claim 2 which implements the said absorption rate improvement assistance process using the said modeling light beam and the said assistance light beam. The absorption rate improvement support unit performs the absorption rate improvement support process using the support light beam without using the modeling light beam,
The said modeling part is a manufacturing apparatus of the molded article of Claim 2 which implements the said modeling process using the said modeling light beam, without using the said assistance light beam. The absorption improvement support process is a process of forming an oxide film on the surface of the metal powder,
The absorptance improvement support unit irradiates the support light beam to a first irradiation position within the irradiation range of the metal powder with a first spot diameter, and simultaneously applies the modeling light beam to the first irradiation position. The oxide film is formed by irradiating the assist light beam with a spot diameter in an overlapping manner,
The said modeling part irradiates at least the said modeling light beam with said 1st spot diameter to said 1st irradiation position which is a formation position of the said oxide film, and implements the said modeling process. The manufacturing apparatus of the molded article described in the item. The absorption improvement support process is a process of forming an oxide film on the surface of the metal powder,
The absorptance improvement support unit forms the oxide film by irradiating the support light beam to a second irradiation position in the irradiation range of the metal powder with a second spot diameter,
The said modeling part manufactures the modeling object of Claim 5 which irradiates the said 2nd irradiation position which is the formation position of the said oxide film with the said 2nd spot diameter, and performs the said modeling process. apparatus. The absorption improvement support process is a process of forming an oxide film on the surface of the metal powder,
The absorptance improvement support unit irradiates the support light beam to a third irradiation position within the irradiation range of the metal powder with a third spot diameter, and at the same time, the modeling light beam is smaller in diameter than the third spot diameter. By irradiating the assist light beam with a fourth spot diameter, the oxide film is formed,
5. The modeling object according to claim 2, wherein the modeling unit performs the modeling process by irradiating at least the modeling light beam to the formation position of the oxide film with the fourth spot diameter. manufacturing device. The absorption improvement support process is a process of preheating the metal powder and forming an oxide film on the surface of the metal powder after preheating,
The absorption rate improvement support unit
Irradiating at least the assisting light beam at the fifth irradiation position within the irradiation range of the metal powder with the fifth spot diameter before irradiation of the modeling light beam, and performing a pre-heat treatment,
The assisting light beam is irradiated to the fifth irradiation position within the irradiation range of the metal powder with the fifth spot diameter, and at the same time, the modeling light beam is applied with the sixth spot diameter smaller than the fifth spot diameter. The oxide film is formed by irradiating with the assisting light beam,
The said modeling part is a manufacturing apparatus of the modeling object of Claim 2 or 4 which irradiates the formation position of the said oxide film with the said 6th spot diameter at least with the said modeling light beam, and implements the said modeling process.   The said absorption rate improvement assistance part is a manufacturing apparatus of the molded article of Claim 9 which implements the said pre-heat treatment using the said assistance light beam, without using the said modeling light beam. The absorption rate improvement support unit
A film thickness estimation unit that estimates the film thickness of the oxide film formed on the surface of the metal powder by the absorption rate improvement support process;
It is determined whether or not the estimated film thickness of the oxide film has reached a predetermined film thickness, and when it is determined that the predetermined film thickness has been reached, from the absorption rate improvement support process, the modeling unit A process switching determination unit for switching to the modeling process;
With
The film thickness estimation unit is
A surface temperature measuring unit for measuring a surface temperature of the metal powder on which the oxide film is formed;
An irradiation time measuring unit that measures an irradiation time of the support light beam, or the support light beam and the modeling light beam applied to the surface of the metal powder for the formation of the oxide film;
Based on the measured surface temperature and the measured irradiation time, an oxide film thickness calculator that calculates an estimated film thickness of the oxide film,
The manufacturing apparatus of the molded article of any one of Claims 6-10 provided with these. The absorption rate of the modeling light beam with respect to the metal powder is a period in which a maximum value and a minimum value appear alternately with respect to a change in the increasing direction of the film thickness in relation to the film thickness of the oxide film. And having the property of being the smallest when the thickness of the oxide film is zero,
In the absorption rate improvement support unit,
The predetermined film thickness of the oxide film formed beyond the zero is
In relation to the absorptance having the periodicity, it is set within a range of the first maximum film thickness or less corresponding to the first maximum value that exceeds the zero and first appears as the maximum value. The manufacturing apparatus of the molded article of Claim 11. The modeling light beam is near infrared wavelength laser light,
The manufacturing apparatus for a shaped article according to any one of claims 2 to 12, wherein the assisting light beam is a laser beam having a short wavelength shorter than the near-infrared wavelength. The absorption rate improvement support process is a process of forming a black film by attaching a black material to the surface of the metal powder supplied to the irradiation range by the metal powder supply device,
The absorption rate improvement support unit is supplied to the irradiation range by the absorption rate improvement support process before the metal powder is supplied to the irradiation range or after the metal powder is supplied to the irradiation range. The manufacturing apparatus of the molded article according to claim 1, wherein the black film is formed on the surface of the metal powder.   When the modeling part irradiates the surface of the metal powder with the modeling light beam and heats the metal powder and solidifies by sintering or melting after the absorption rate improvement support process is performed, the black color The manufacturing apparatus of the molded article according to claim 14, wherein the coating does not remain in the molded article that is solidified and layered.   The absorption improvement support unit includes a black film forming apparatus that is provided inside the chamber and forms the black film on the surface of the metal powder after the metal powder is supplied to the irradiation range. The manufacturing apparatus of the molded article of Claim 14 or 15. The range in which the absorption rate improvement support unit forms the black film on the surface of the metal powder is:
17. The range corresponding to a predetermined irradiation position where the modeling part irradiates the surface of the metal powder with the modeling light beam in order to perform the modeling process after the absorption rate improvement support process is performed. The manufacturing apparatus of the molded article described in 2.   The black film is formed on the surface of the metal powder by the absorptance improvement support unit every time after the metal powder is supplied to the irradiation range by the metal powder supply device. The manufacturing apparatus of the molded article of Claim 1. The absorption rate improvement support unit
Before the metal powder is supplied to the irradiation range, the black material is mixed into the metal powder aggregate that is a raw material of the metal powder and stirred to adhere to the surface of the metal powder to form the black film. The manufacturing apparatus of the molded article of Claim 14 or 15.   The said black material which forms the said black membrane | film | coat is carbon black, The manufacturing apparatus of the molded article of any one of Claims 14-19.   The said modeling light beam is a manufacturing apparatus of the modeling object in any one of Claims 14-20 which is a laser beam of a near-infrared wavelength.   The said metal powder is a copper powder, The manufacturing apparatus of the molded article of any one of Claims 1-21. It is a manufacturing method of a shaped article that is solidified by sintering or melting a metal powder by irradiation with a modeling light beam,
A metal powder supply step of supplying the metal powder to the irradiation range of the modeling light beam;
In order to improve the absorption rate of the shaped light beam to be irradiated into the metal powder, an absorption rate improvement support step for performing a predetermined absorption rate improvement support process on the metal powder;
After execution of the absorption rate improvement support process, the modeling light beam is irradiated to the metal powder supplied to the irradiation range, the metal powder is heated, solidified by the sintering or melting, and the layered modeling is performed. A modeling process for processing,
The manufacturing method of a molded article provided with. The absorption rate improvement support process includes:
The surface of the metal powder to be supplied to the irradiation range by the absorption rate improvement support process performed before the metal powder is supplied to the irradiation range or after the metal powder is supplied to the irradiation range. The method for manufacturing a shaped article according to claim 23, wherein a black film is formed.

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