JPS5856768A - Manufacturing method for rotary dressor - Google Patents

Abstract

PURPOSE:To enhance the strength of joint with core by placing a molded body of ferric base powder in the center of a negative die and by filling it with powder consisting of tungsten etc. CONSTITUTION:Super abrasive grain 2 is lightly attached to a circular surface of a negative die 1, and in its center a circular molded body 10 of ferric base powder with specified dimensions is inserted, where metal dust 5 with good heat and abrasion resistance such as tungsten shall fill the space between the surface 2 of this negative die 1 and the outside circumferential surface of this molded body 10, over which an infiltrating material 6 is placed, whereafter the whole is heated to exceed the melting point of this infiltrating material 6 to melt the infiltrating material 6 which is then infiltrated into gaps between powder particles of the molded body 10 and the metal dust 5. Thereby the strength of joint between the outer layer of base metal formed through sintering of tungsten powder etc. and the inner layer of the core formed by the molded body of ferric powder.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a rotary dresser. There are two types of methods for manufacturing rotary dressers: electroplating and sinter infiltration.

The former is diamond grain; fc is cubic boron nitride (C
Super abrasive grains such as BN) are fixed with a metal layer by electroplating, and there are two types: an inverted electrodeposition type and a single layer type on the surface.

On the other hand, the latter is made by fixing superabrasive grains such as diamond or CBN with sintered metal, and some have superabrasive grains only on the surface, while others have superabrasive grains distributed from the surface to a certain depth. There is something.

The present invention relates to the latter, that is, an IB manufacturing method using sintering and standing.

First, an outline of the conventional manufacturing method by sintering and dipping will be explained.

FIG. 1 shows a negative mold 1 (forming mold) of a rotary dresser that includes a grinding face metal and has a graph 1 pattern. The mold Iki (inner peripheral surface) 2 of this negative mold 1 is made to adhere to super abrasive grains such as diamond or CBN.
As shown in FIG. 2, insert and assemble the core 4, and fill the space between the mold surface 2 of the negative mold I and the outer peripheral surface of the core 4 with metal powder
Fill it. If the infiltrant 6 is placed on top of the metal powder 5 and the entire body is heated above the melting point of the infiltrator 6, the infiltrate d6 will melt and fill the gaps between the filled metal powder 5. After that, it is cooled and solidified to integrate the superabrasive grains 2 and the metal powder 5 to form an infiltrated body.

If unnecessary negative mold I, core 4, etc. are removed and finished to the specified dimensions and shape, superabrasive grain 1f as shown in Figure 3 is obtained.
A rotary dresser having i7ffi is obtained.

By the way, since the metal powder 5 must be able to withstand high temperatures and have high abrasion resistance, a hard metal powder such as tungsten is usually used, but in order to save on the use of this expensive metal powder. As shown in FIG.
The space between the core 8 and the outer circumferential surface of the core 8 is filled as much as possible with metal powder 5 such as tungsten, and after going through the above-mentioned infiltration process, the core 8 is finally transferred to a rotary dresser with 6flB.
In some cases, it can be completed as An example of a rotary dresser manufactured by such a method is shown in FIG. 5, and as is clear from the figure, the core 8 made of iron or iron alloy
A sintered base metal 9 made of tungsten or the like is molded and fixed on the outer peripheral surface of the rotary dredge nose having 7 superabrasive grain surfaces on the surface of the sintered base metal 9.

As explained above, by using an iron core, the use of expensive powder such as tungsten can be completely saved.

However, when all the cores are replaced as described above, the core 8 and the sintered base metal 9 are essentially different metal materials, and the bonding strength between the two is different from that of the core 8 and the sintered base metal 9. It is equal to the brazing strength at the boundary between As a result, the bonding strength between the core 8 and the sintered base metal 9 is weak, and there is a risk that the core 8 and the sintered base metal 9 will often come out of joint. Because they are different types of materials and their coefficients of thermal expansion are usually significantly different,
During the cooling process after infiltration, significant strain was caused in the same area, and superabrasive grain 1
This will induce distortion at 1i7 and lower the top of the rotary dresser.

Therefore, in the manufacturing method of the present invention, as shown in FIG. An annular iron-based powder molded to a predetermined size in the center of the mold l, the molded body IO is inserted and assembled instead of the aforementioned core 8, and the mold surface 2 of the negative mold 1 and the iron-based powder molded body 10 are assembled. The space between the outer peripheral surface and the outer surface is filled with a metal powder 5 having high heat and wear resistance such as tungsten, and an infiltrant material 6 whose main components are, for example, copper, nickel, and zinc is placed on top of this powder to completely infiltrate the entire surface. The infiltrant material 6 is heated to a temperature higher than the melting point of the material 6 to melt it and penetrate into the gaps between the powder particles of the metal powder 5' and the iron-based powder compact 10. After this infiltration work is completed and the infiltrant material 6 is solidified, it is removed from the negative mold 1 and finished to a predetermined dimensional accuracy, thereby obtaining a rotary dresser according to the manufacturing method of the present invention.

The infiltrant 6 may be placed on the filled metal powder 5 as shown in FIG. 4, or it may be placed on the iron-based powder compact IO as shown by the dotted line.

The iron-based powder compact 10 is a powder compact made of a composition containing iron powder or iron alloy powder as a main component, and additional elements such as copper, nickel, carbon, etc. that are commonly used in steel or powder metallurgy. It can be used by pre-sintering it, or it can be used unsintered.

0 Note that this iron-based powder compact may or may not be infiltrated.

As explained above, the present invention uses an iron-based powder sintered body as a core to reduce the bonding strength with the part that will become the gold 4 powder sintered core made of tungsten powder or the like.
- In order to compare with the conventional one, we prototyped the one according to the present invention and the one according to the conventional example and compared the bonding strength fc. As a prototype, Ya 1↓ [Secret 1w8.8? A tungsten powder filling of /crtl was brought into contact with the specimen shown in Table 1, and an infiltrant containing copper-nickel-zinc (melting point: 890°C) as a main component was placed on the filling, and the whole was heated in a protective air flow. The infiltrant was heated to 1080° C. to completely melt it and infiltrate into the tungsten powder, and at the same time, the tungsten powder infiltrated body was joined to the specimen. After solidification and cooling, the bonding strength rw-+ between the tungsten powder infiltrated body and the specimen was measured.

In addition, 525C in Table 1 is carbon steel shown in JIS.

If the 525C in Table 1 above is used with nickel or copper plating, it will have a 2-
It can be seen that the bonding strength is improved three times.

On the other hand, it can be seen that in the case of the present invention, the improvement is more than 10 times that in the case of no treatment of 525C.

The above results will be explained using schematic diagrams shown in FIGS. 6 and 7.

FIG. 6 shows an example in which an iron alloy compact is used as the core, and FIG. 7 shows an example in which an iron-based alloy powder compact of the present invention is used.

In FIG. 6, the iron or iron alloy molded body 3 and the powder grains 11 of tungsten or the like are joined by an infiltration material 12.
The bonding strength of this portion can be greater than the brazing strength between the iron alloy molded body 9 and the infiltrant material 12, and it is inevitable that the bonding strength will be reduced due to voids 13 due to poor wetting that often occurs.

On the other hand, in FIG. 7, an iron-based powder molded body is used as the core, and the infiltrant material 12 is powder particles 14 of iron or the like.
and powder particles 11 of tungsten or the like are connected and bonded together in a complete network structure.

In Clothing 1, the apparent density of the iron-based powder molded body (however, a material with an apparent density of 5.9 t rttlQ is used after grinding, but if the apparent density is 3.0 t / ad or less, the strength as a component is insufficient. If it exceeds 7.2 f/cttl'jE, the porosity will drop significantly and infiltration will not be carried out satisfactorily, so it is necessary to set the density within this range during molding.

1 Furthermore, as additional elements to the iron powder, copper 0.01 to 20%, 0.0196% or less, the addition effect is difficult to recognize, and 2(li), the pores of the powder compact will be crushed, nickel 0.01 〜10%・・・・・・ If it is less than 0.01%, the effect of addition is small. Carbon 0.01～4.596・・・・・・0.01
If it is less than i%, the effect of the addition will not be noticeable, and if it exceeds 4.596, it will tend to have a cast iron composition and its strength will deteriorate.For the above reasons, it goes without saying that t of the additive element is limited. Nor.

Moreover, molybdenum powder or the like can be used instead of the tungsten powder to be filled.

As explained above, it is possible to significantly increase the bonding strength between the outer layer of the base metal made of sintered tungsten powder and the inner layer of the core made of iron-based powder compact, and the entire body is formed as a powder infiltrated body. Because of its structure, it has a large damping capacity for imaging, and does not cause abnormal vibrations during use. There is no distortion, and once you get used to it, you can write all the details on the rotary dresser with different degrees of accuracy.

[Brief explanation of the drawing]

FIGS. 1 and 2 show the manufacturing process of a conventional rotary dresser using a negative mold. FIG. 3 shows a cross section of a rotary dresser produced by the manufacturing process shown in FIGS. 81 and 2. FIG. 4 is a general explanatory view of manufacturing a rotary dresser integrally having a shell according to the conventional method and the present invention. FIG. 5 shows a cross section of a conventional rotary dresser having an iron or iron alloy molded body as a core. FIG. 6 is a schematic view showing the boundary between the iron or iron alloy molded body and the tungsten powder sintered alloy of the rotary dresser shown in FIG. 5. FIG. 7 is a schematic diagram showing a portion including the boundary between the iron-based powder compact according to the present invention and the alloy formed by sintering tungsten powder. 1... Negative type, 2... Negative type surface,
3... Super abrasive grain, 4... Core, 5... Powder such as tungsten, 6... Infiltration material, 7... Super abrasive stone, 8AA.
... Core (molded body) made of iron or iron alloy, 9...
Sintered base metal, 11... Powder grains such as tungsten, 12...
・Infiltration material, 13...Vacancies, 14...Powder particles such as iron. Procedural amendment document January 1980 Director General of the Japan Patent Office Shima 1) Haruki Tono1, Case description 2, Name of the invention study group Method for manufacturing rotary dressers 3 Person making the amendment Relationship to the case Patent applicant address 2780 Hohokucho, Sakai City Name Osaka Diamond Industry Co., Ltd. 5 Date of amendment order Voluntary amendment (1) Specification Detailed description of the invention column (2) Drawing 7 Contents of amendment (1) Immediately below No. 9 of the specification Insert "Do" next to "Intensity is low" in the fourth line. (2) Amend Figure 6 of the drawing to a separate drawing. Procedural amendment 1, Indication of case 2, Name of invention consideration Method for manufacturing rotary dresser 3, Person making the amendment Relationship with the case Patent applicant address 2-80-s Otori Kita-cho, Sakai City Place name Osaka Diamond Kogyo Co., Ltd. Company 4, agent address: 1-9-20 Nishinakajima, Yodoyo-ku, Osaka City, 5, amendment 4
Voluntary amendment to the date of the FI order 6 Scope of claims to be amended Column for detailed description of the invention Column for brief explanation of drawings Column 7 Contents of amendment (1) Specification, page 5, line 10, “Super-abrasive Correct "Grain 2" to "Super Abrasive Grain 3". (2) Same page 10, No. 3? 'T', correct it as "outer layer" and "inner layer". (3) In the 4th line of No. 10, "inner layer" is corrected to "outer layer." (4) In the 9th line of the 11th text, "super abrasive surface" [corrected as super abrasive surface j]. (5) In the 10th line of No. 11, insert "10... iron-based powder compact" after "sintered association." (6) The entire scope of claims shall be corrected as shown in the appendix. (1) Super abrasive grains such as diamond or Q or CBN are adhered to the mold surface of the Nekateib mold, and an iron-based powder compact is placed on the instep of the Maekiteib mold. A heat-resistant surface rich in powder such as tungsten or the like is filled between the mold surface of the Kateib mold and the outer surface of the iron-based powder molded body, and a bath is applied to this material. Rotor 11-dreno→)σ) manufacturing method characterized by caloric infiltration, superabrasive grains, tungsten, etc. (2) 1!8! of the one-mouth dresser according to claim 1, which is characterized in that the iron-based powder compact is not pre-sintered; Construction method. (3) A method for manufacturing a rotary dresser according to claim 1, characterized in that an unsintered compact is used as the iron-based powder compact.

Claims (3)

[Claims] (1) Diamond or C on the negative mold surface
A super abrasive grain such as BN is made to adhere to the iron-based powder compact, and an iron-based powder compact is placed in the center of the negative mold. Fully filled with heat-resistant and wear-resistant powder, which is then heated and infiltrated with an infiltrating material, and then the powder filling made of super abrasive grains, Ta/Guste/etc. A manufacturing method for a rotary dresser that features integrated ridges. (2) Claims 1 and 7 characterized in that the iron-based powder compact is one that has undergone pre-tempering #f.
A method for manufacturing a rotary dresser according to item 2 of 'cjyu. (3) A method for manufacturing a rotary dresser according to claim 1 or 2, characterized in that an unsintered compact is used as the iron-based powder compact.