JPS63192540A - Manufacturing method and equipment for thin plates - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for manufacturing a thin plate suitable for directly manufacturing a thin plate from a molten substance and obtaining a thin plate having high surface accuracy and excellent mechanical properties. and its manufacturing equipment.

[Conventional technology]

Methods for directly manufacturing thin plates from molten materials can be broadly divided into single roll method and twin roll method. Each has its advantages and disadvantages, and the twin-roll method is superior to the single-roll method in terms of surface precision (surface roughness). However, even when manufactured by the twin roll method, it is not possible to obtain the surface precision of generally commercially available rolled materials such as stainless steel and aluminum-steel-nickel alloy (hereinafter referred to as commercially available materials). In order to obtain surface precision equivalent to that of commercially available materials, it is necessary to repeat rolling, sintering, and rolling. Further, the mechanical properties of the thin plates produced by these methods are not expected to be significantly improved because the structure is columnar crystals. This will be specifically explained based on the drawings.

FIG. 14 shows the conventional single roll method. The cross-sectional structure of the thin plate 5 manufactured by the single roll method is a structure in which columnar crystals are developed from the surface in contact with the roll 2 (lower surface in the figure), as shown schematically in FIG. 1 indicates a nozzle for supplying the molten substance.

FIG. 16 shows the twin roll method. FIG. 17 is a schematic diagram of the cross-sectional structure of the thin plate 5 manufactured by the twin roll method. In the twin roll method, the molten material is cooled by the two rolls 2, so columnar crystals develop from both sides of the thin plate 5, and these crystals form -A in the center.
There are 245. However, the thickness of the thin plate produced by this method is about 2 mm, and is not intended for thin plates of 1 m or less as in the method of the present invention. Therefore, rather than surface roughness, the thickness variation is as much as ±0.5 nm. This method uses continuous casting to manufacture approximately 2mm pieces, and then rolling →
This manufacturing method is based on repeating annealing and rolling to achieve surface precision equivalent to commercially available materials.

Furthermore, FIG. 18 shows another conventional device. This conventional device has a structure in which a main moving cooling body 2 and a sub moving cooling body 3, which are rolls, are pressurized by a hydraulic cylinder 4 and rotate in contact with each other. Due to this contact structure, it is difficult for the molten substance to be bitten smoothly, and the roll is also easily damaged.

[Problem that the invention seeks to solve]

As mentioned above, the thin plates produced by the conventional single roll method and twin roll method have low surface precision, and in order to improve the surface precision, the steps of rolling→annealing→rolling are required, resulting in an increase in the number of steps. Furthermore, since the crystal structure of the thin plate manufactured by this method is a columnar crystal structure (FIGS. 15 and 17), there is a problem that mechanical properties such as elongation are inferior. Furthermore, the thin plate produced by the apparatus shown in FIG. 18 also has the problem of low surface accuracy.

An object of the present invention is to provide a method for manufacturing a thin plate with high surface precision and excellent mechanical properties directly from a molten material.

Another object of the invention is to provide a thin plate manufacturing apparatus that can easily carry out the above method.

[Means and effects for solving the problem] The present invention supplies a molten material, which is a thin plate material, to a main moving cooling body with a curved surface, starts cooling and solidifying from the contact surface, and then melts the material on the opposite surface. In this method, the unsolidified layer side is cooled and solidified by a sub-moving cooling body having a gap with the main moving cooling body while the unsolidified layer remains, and simultaneously rolled by a pair of re-cooling bodies.

As a result, cooling of the unsolidified layer and rolling of the entire body are performed at the same time and in a state where the deformation resistance of the rolled material is small due to the gap, improving the surface precision and inhibiting the growth of columnar crystals to form a fine crystal structure. Therefore, the mechanical properties of the thin plate are improved.

Another invention provides a nozzle for supplying a molten material, which is a thin plate material, a main moving cooling body having a curved surface disposed directly below the outlet of the nozzle, and a main moving cooling body having a curved surface shape, and the molten material being cooled and solidified on the main moving cooling body. This is a thin plate manufacturing apparatus comprising a main moving cooling body and a secondary moving cooling body having a curved surface, which is disposed at a position where an unsolidified layer of molten material remains, with a gap therebetween, through which a rolling pressure is applied to the molten material.

This makes it possible to roll the material to be rolled with low deformation resistance simply by supplying the molten material onto the main moving cooling body, thereby making it possible to manufacture thin sheets with good surface accuracy and good mechanical properties. It is.

〔Example〕

FIG. 1 is a configuration diagram of a manufacturing apparatus according to the present invention.

The large-diameter main moving cooling body 2 and the small-diameter auxiliary moving cooling body 3, both of which have curved surfaces, are pressurized by a hydraulic cylinder 4 without contact through a gap, but both cooling bodies 2 and 3 are not shown. It is rotated by a drive device. The nozzle 1 is installed directly above the main moving cooling body 2. Although the gap between the main and auxiliary moving cooling bodies 2.3 is not shown, it is adjusted with a gap spacer so that a desired rolling pressure can be obtained.

The purpose of non-contact is to allow the molten substance to be smoothly caught between the main and auxiliary moving cooling bodies 2 and 3, and also to prevent the occurrence of scratches on both the cooling bodies 2 and 3, which are rolls.

It is not possible to manufacture a thin plate with high surface accuracy by simply doing this, and the most important thing is that at the time when it is caught between the main and sub moving cooling bodies 2 and 3, a part of the molten material on the surface in contact with the sub moving cooling body 3 is removed. It is in an uncoagulated state. Here, the uncoagulated state is (
1) A state in which the liquid phase and the same phase are mixed, or (2) a state in which the liquid phase is supercooled. By maintaining this unsolidified state, deformation resistance is reduced, and the entire surface is rolled uniformly, making it possible to manufacture a thin plate with high surface precision equivalent to that of commercially available materials. Furthermore, as will be described later, by rolling the thin plate in a partially unsolidified state, the structure of the thin plate has the effect of becoming a fine structure with fewer columnar crystals.

Here, when the unsolidified portion is finally manufactured into a thin plate, its structure will not be a columnar crystal but a fine structure, so the location of the sub-moving cooling body 3 was originally The position of the cooling body 3 is changed, and its optimum position is determined from the structure of the thin plate corresponding to each position. Here, the optimal position is such that the thickness of the solidified layer (columnar crystals) in which the molten material comes into contact with the main moving cooling body 2 and is cooled and solidified is equal to the thickness of the thin plate rolled between the main and auxiliary moving cooling bodies 2 and 3. This is the position where the amount is 1/2 or less. As a result, more than half of the structure of the thin plate becomes a fine structure, so that the mechanical properties can be significantly improved. Incidentally, even if the fine structure is less than half, the mechanical properties are improved compared to a thin plate produced using conventional manufacturing equipment, so the proportion of the fine structure may be determined depending on the intended use of the thin plate.

Further, the gap is determined to such an extent that a rolling pressure that can improve surface accuracy can be obtained. There is no particular limitation, but from 1 ton to 100
A desired surface precision can usually be obtained by appropriately setting it within a range of approximately 100,000 ton.

Figures 2(a)-(d) illustrate devices according to various aspects of the invention. The figure shows the process in which the molten material ejected from the nozzle 1 is rolled between the main and auxiliary moving cooling bodies 2 and 3 to produce the thin plate 5.

The space between the auxiliary moving cooling bodies 2 and 3 is pressurized and rotated without contact, which is a feature of the present invention. That is, in both embodiments, a gap is provided in which the unsolidified layer remains and is cooled and rolled by both cooling bodies 2 and 3 to obtain a rolling pressure that improves the surface accuracy.

FIG. 3 shows the process of manufacturing a thin plate using the apparatus of the present invention. The main moving cooling body 2 and the auxiliary moving cooling body 3 rotate synchronously while being pressurized without contact, and the gap between the main and auxiliary moving cooling bodies 2 and 3 is determined by the proportion of the unsolidified layer at that position. It is determined by the thickness of the sheet to be manufactured. The molten substance 6 ejected from the nozzle 1 comes into contact with the main moving cooling body 2, and solidification begins from that surface to form a solidified layer 7. On the other hand, the molten material on the side of the secondary moving cooling body 3 opposite to this surface forms an unsolidified layer 8, and in this state it is rolled and cooled between the main and secondary moving cooling bodies 2 and 3 as shown in Fig. 4 (Thin plate width As shown in the schematic diagram of the cross-section in the direction), it is possible to produce a thin plate with smooth surfaces on both sides that are in contact with the main and sub-moving cooling bodies 2 and 3, and with high surface precision equivalent to that of commercially available materials, and with a fine structure. The reason why the unsolidified layer portion has a fine structure is that it is solidified in a supercooled state between the two coolants 2.3. FIG. 5 shows a schematic cross-sectional view of the thin plate at the time when it is inserted between the main and sub-moving cooling bodies in the width direction. The thickness of the solidified layer 7 on the main moving cooling body side that has solidified in contact with the main moving cooling body 2 is 1/2 or less of the thickness of the same thin plate, and the rest is an unsolidified layer as shown in Figure (a). is desirable. If this is not the case, the microstructure proportion of the produced sheet metal will be reduced and the mechanical properties will not be sufficiently improved. If the unsolidified layer is less than 175, the surface precision tends to be insufficient, so it is desirable to set it within the above range. FIG. 5(b) shows the case where the thickness of the coagulated layer 7 is 1/2 or more,
In this case, as described above, since the thickness of the unsolidified layer 8 is small, the deformation resistance is high and the surface accuracy tends to be incomplete. In the case shown in FIG. 3(c), there is no unsolidified layer and only the solidified layer 7 is present. In this case, the deformation resistance is high and the roll cannot be rolled with the same rolling load as in (b) above, resulting in damage to the roll.

The thickness of the thin plate to be manufactured is preferably 1+nm or less.

This is because, although it depends on the viscosity of the material, it is usually difficult to maintain a molten material of 1 rrIn or more until it is caught between the main and auxiliary moving cooling bodies. Furthermore, in order to obtain high surface precision equivalent to that of commercially available materials using the method of the present invention, it is desirable that the surface roughness of the surfaces of the main and sub-moving cooling bodies 2 and 3 in contact with the molten material 6 be ±0.25 μm or less. In order to obtain this value, it is preferable to use a hard material, and from the viewpoint of wear resistance, Rc is preferably 50 or more.

This is because the surface roughness of the manufactured thin plate is transferred from the surface roughness of the main and auxiliary moving cooling bodies described above. Therefore, the surface roughness of the manufactured thin plate is also less than ±0.25 μm. The material of the main and sub moving cooling bodies is preferably 5KD-61&Il, which is made of alloy tool steel and has excellent heat crack resistance.

Figure 6 shows the present invention method and the conventional method (twin roll method, single roll method)
An example comparing the surface roughness of thin plates manufactured by The surface roughness of the roll is the same for both the method of the present invention and the conventional method. As is clear from the figure, according to the present invention, the surface roughness is 0.2 μm. This value is equivalent to that of commercially available materials (aluminum, copper, stainless steel, etc.).

FIG. 7 shows a case where the thin plate manufacturing method does not satisfy the method of the present invention. That is, when the molten material is rolled between the main and auxiliary moving cooling bodies 2.3, the proportion of the solidified layer 7 is almost all, and the proportion of the unsolidified layer 8 is 115 or less. In this case, a rolled part 13 and an unrolled part 14 are present on the sub-moving cooling body side as shown in the cross-sectional schematic diagram in FIG. 8, and a thin plate with a high surface area cannot be manufactured. Furthermore, there is almost no fine structure.

FIG. 9 compares the surface roughness of thin plates manufactured by the methods shown in FIGS. 3 and 7 using the manufacturing apparatus of the present invention. According to the manufacturing method shown in FIG. 3, the surface roughness of the thin plate is equivalent to that of commercially available materials. However, it is understood that a thin plate with a high area density cannot be manufactured unless the manufacturing method of the present invention is satisfied.

FIG. 10 shows another embodiment of the thin plate manufacturing apparatus.

The middle moving cooling body 3 and the nozzle 1 are formed so as to be able to approach and separate from the main moving cooling body 2, and the sub moving cooling body 3 approaches a predetermined gap position after a predetermined time has elapsed after the start of molten material supply,
A control unit (not shown) is provided for separating the sub-moving cooling body 3 and the nozzle 1 from the main moving cooling body 2 at the end of thin plate manufacturing. At the beginning of the ejection of molten material, a steady flow cannot be obtained and a turbulent flow tends to occur. Therefore, when this is rolled, the roll is easily damaged.

Therefore, as shown in FIG. 2(a), the secondary moving cooling body 3 is opened for a predetermined period of time at the initial stage of ejection, and the load is applied only after a steady flow is achieved as shown in FIG. 2(b).

The final stage of ejection tends to become turbulent, and after the ejection ends, the molten material 6 adheres to the tip of the nozzle and solidifies, so this solidified material comes into contact with the main moving cooling body 2, causing damage to the nozzle 1.
and cause damage to the roll. Therefore, the same figure (
As shown in c), when the load on the auxiliary moving cooling body 3 is released, the nozzle 1 rises upward so that it does not come into contact with the main moving cooling body 2.

FIG. 11 shows yet another embodiment of the invention. The smaller the diameter of the sub-moving cooling body 3, the higher the Hertzian stress.
The pressurizing load between the main and auxiliary moving cooling bodies 2 and 3 can be low. However, making it smaller makes the cooling structure difficult. Therefore, as shown in the figure, a sub-moving cooling body 3 made of a steel belt may be wound between the rolls 9 and 10. This makes it possible to cool the steel belt with the water cooling spray 12,
Since the inside of the auxiliary moving cooling body does not need to have a water-cooled structure as in the conventional case, its diameter can be reduced. The duster 11 is used to clean the surface of the steel belt that has been wetted by the water-cooled spray 12. Note that the steel belt may be attached to the main moving cooling body 2 side, or may be attached to both the main and auxiliary moving cooling bodies 2 and 30.

[Experimental Example 1] A thin plate was manufactured using the manufacturing apparatus shown in FIG. 1 of the present invention under the manufacturing conditions shown below.

1) Shape of main moving cooling body: diameter 800rrtn, width
500mm, Main moving cooling body material: Made of alloy tool steel (SKD-61 steel), Internal water cooling structure, Hardness is Hv 53, Main moving cooling body surface roughness 20.2μm, 2) Sub-moving cooling body Shape: Diameter 300mm, Width 50mm
0 ■, Material of sub-moving cooling body: Made of alloy tool steel, internal water cooling structure, Surface roughness of sub-moving cooling body: 20.2 μm, 3) Nozzle material: Made of alumina Dimensions of nozzle opening: 1 mm l mm x 200 n Molten substance: Cu - A n -N i alloy 5) Ejection temperature of molten material and pressure crab 1200℃ 0.1 kg/cJ 6) Circumferential speed of main and auxiliary moving cooling bodies: 5 m/s 7) Gap between main and auxiliary moving cooling bodies: 0 .05mm8) 50 tons of pressurized crab between the main and sub moving cooling bodies As a result, a thin plate with a width of 200mm and a thickness of 0.3mm was manufactured. When the surface roughness of the thin plate was measured, it was found to be 0.2 μm, which was a high surface accuracy. Figure 12 compares the mechanical properties of this thin plate and a thin plate manufactured by the conventional method.Cu-AΩ-Ni alloy is a difficult-to-process material and is a very brittle material, but the device and manufacturing method of the present invention According to the method, it was found that the elongation was improved compared to the conventional method. This is thought to be due to the fact that there are fewer columnar crystals and the structure is finer, which improves elongation.

[Experimental Example 2] A thin plate was produced using the method of the present invention using stainless steel as the molten material, the ejection temperature was 1550'C1, the ejection pressure was 0.2 kg/cJ, and the other manufacturing conditions were the same as in Experimental Example 1. As a result, a thin plate with a width of 200 nm and a thickness of 0.35 mm was manufactured. The surface roughness of the thin plate was 0.2 μm, and the surface accuracy was high.

FIG. 13 shows the X-ray diffraction patterns of thin plates produced by the conventional single roll method and the method of the present invention. In both cases, production was carried out in the air, and in the case of the conventional method, in addition to the peak of the austenite phase, a peak of oxides due to oxidation was observed. However, in the present invention, these oxide peaks do not appear, and it is clear that the method of the present invention is superior.

〔Effect of the invention〕

According to the manufacturing method of the present invention, the cooling of the unsolidified layer and the rolling of the entire body are carried out simultaneously and in a state where the deformation resistance of the rolled material is small due to the gap, so that the surface precision of the thin plate can be improved and the columnar crystals can be reduced. Growth can be inhibited to form a fine crystalline structure, thus improving the mechanical properties of the thin plate.

Further, according to the manufacturing apparatus of the present invention, the above method can be easily carried out by simply supplying the molten substance onto the main moving cooling body, and the structure is also simple.

In any of the inventions, the conventional repeating process of rolling → annealing → rolling can be omitted, so the number of man-hours can be reduced and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the manufacturing apparatus according to the present invention, FIGS. 2(a) to (d) are block diagrams showing different aspects of the manufacturing apparatus according to the present invention, and FIG. 3 is a block diagram showing an embodiment of the manufacturing apparatus according to the present invention. FIG. 4 is a schematic diagram showing a cross section of a thin plate manufactured by the manufacturing apparatus of the present invention, and FIGS.
(c) is a cross-sectional view showing the different states of the molten material before rolling; FIG. 6 is a comparison diagram showing the surface roughness of thin plates produced by the method of the present invention and the conventional method; FIG. Fig. 8 is a schematic cross-sectional view of a thin plate manufactured by the method shown in Fig. 7, and Fig. 9 shows the manufacturing method of the present invention and a method different from the method of the present invention using the manufacturing apparatus of the present invention. 10(a) to 10(c) are configuration diagrams of other embodiments of the manufacturing apparatus according to the present invention in different states;
Figure 1 is a schematic diagram showing different embodiments, Figure 12 is a comparison diagram showing the mechanical properties of thin plates manufactured by the method of the present invention and the conventional method, and Figure 13 is a diagram of stainless steel manufactured by the single roll method and the method of the present invention. A comparative diagram showing the X-ray diffraction patterns of , Fig. 14 is a configuration diagram showing the production equipment using the single roll method, Fig. 15 is a schematic cross-sectional diagram of a thin plate produced by the single roll method, and Fig. 16 is a diagram showing the cross section of the thin plate produced by the twin roll method. FIG. 17 is a schematic cross-sectional view of a thin plate manufactured by the twin roll method, and FIG. 18 is a configuration diagram showing another conventional example. DESCRIPTION OF SYMBOLS 1... Nozzle, 2... Main moving cooling body, 3... Sub-moving cooling body, 4... Hydraulic cylinder, 5... Thin plate, 6
...Melted substance, 7. Solidification phase, 8. Semi-all phase, 9. Roll, 10. Roll, 11. Duster, 12. Water-cooled spray.

Claims (1)

[Claims] 1. A molten material, which is a thin plate material, is supplied to a main moving cooling body having a curved surface, and cooling and solidification is started from the contact surface, with an unsolidified layer remaining on the opposite surface. A method for manufacturing a thin plate, characterized in that the unsolidified layer side is cooled and solidified by a sub-moving cooling body having a gap with the main moving cooling body, and at the same time rolling is performed by a pair of both cooling bodies. 2. In claim 1, the thickness of the solidified layer obtained by cooling and solidifying the molten material in contact with the main moving cooling body is 1/2 of the thickness of the thin plate rolled between the main and auxiliary moving cooling bodies. A method of manufacturing a thin plate as follows. 3. A nozzle for supplying a molten substance that is a thin plate material, a main moving cooling body with a curved surface disposed just below the outlet of this nozzle, and a main moving cooling body with a curved surface shape, and the molten substance being cooled and solidified on this main moving cooling body. 1. An apparatus for manufacturing a thin plate, comprising a main moving cooling body and a sub moving cooling body having a curved surface, which is disposed at a position where an unsolidified layer remains, with a gap through which a rolling pressure is applied to the molten material. 4. In claim 3, the auxiliary moving cooling body and the nozzle are formed so as to be able to approach and separate from the main moving cooling body, and the auxiliary moving cooling body moves to the gap position after a predetermined time elapses after the start of molten material supply. A thin plate manufacturing apparatus, comprising: a control unit that approaches a main moving cooling body and separates a sub-moving cooling body and a nozzle from a main moving cooling body when manufacturing of the thin plate is completed. 5. In claim 3, manufacturing a thin plate in which at least one of the main moving cooling body and the auxiliary moving cooling body is a steel belt wound around a roll, and a water cooling spray is provided to cool the steel belt. Device.