JPH0669570B2 - Method for manufacturing thin metal plate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method of stretching a plate-shaped material in one direction to manufacture an intermediate thin plate, and rolling the intermediate thin plate in a direction substantially perpendicular to the one direction to obtain a predetermined thickness. The present invention relates to a method for manufacturing a thin metal plate having a plate thickness, and particularly to a technique for efficiently manufacturing such a thin metal plate.

2. Description of the Related Art When a metal thin plate such as a strip is manufactured from a plate-shaped material, it is common that the plate-shaped material is stretched to a desired plate thickness by forging or rolling. However, the metal thin plate thus obtained usually has a fibrous structure that is long in the stretching direction, and therefore when the thin plate is subjected to secondary processing such as punching or bending, it is It cracked or cracked along parallel directions. Therefore, workability is improved by performing an annealing treatment prior to such secondary processing to recrystallize the metal and adjust the crystal structure. For example, W (tungsten) is used. However, metals such as Mo (molybdenum) have a disadvantage that their crystal grains are coarsened by recrystallization and become extremely brittle, making it impossible to perform processing at room temperature.

On the other hand, there is known a method of changing the drawing direction during the drawing process in order to eliminate the directionality of the fiber structure. this is,
Generally called a cross roll, the plate-shaped material is stretched in one direction to produce an intermediate thin plate, and then the intermediate thin plate is rolled in a direction substantially perpendicular to the one direction to obtain a predetermined plate. This is a method for manufacturing a thick metal thin plate. According to this method, it is possible to manufacture a good thin metal plate having excellent workability even with a metal material such as tungsten or molybdenum to which the above-mentioned annealing treatment cannot be applied.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a conventional cross roll, the width dimension of the intermediate thin plate obtained by drawing the plate-shaped material in one direction due to the restrictions of the rolling mill, that is, the direction perpendicular to the drawing direction. Is relatively narrow, and therefore the dimension in the rolling direction when rolling the intermediate thin plate in the direction perpendicular to the one direction becomes short, so that the working efficiency was extremely poor. In particular, in the case of rolling a metal material having a high hardness such as tungsten, the rolling rate must be repeated many times because the rolling rate per pass is small.

Further, since the width of the intermediate thin plate is narrow, the length of the metal thin plate manufactured by rolling in the width direction of the intermediate thin plate is restricted, and the rolling is performed by applying tension in the rolling direction. Since strip rolling becomes difficult, the plate thickness dimension of the metal thin plate was also limited.

Furthermore, since both ends in the rolling direction of the metal sheet thus obtained need to be finally cut, the shorter the length dimension, the lower the yield, and the cutting work requires a long time. This is one of the causes of further lowering the above-mentioned processing efficiency.

Means for Solving the Problems The present invention has been made to solve the above problems, and the gist thereof is that an intermediate thin plate is formed by stretching a plate-shaped material in one direction as described above. After manufacturing the intermediate thin plate, the intermediate thin plate is rolled in a direction substantially perpendicular to the one direction to manufacture a metal thin plate having a predetermined plate thickness. (A) The intermediate thin plate is substantially perpendicular to the one direction. Cutting step for producing a plurality of intermediate thin plate pieces by cutting in different directions, and (b) welding the plurality of intermediate thin plate pieces by abutting their edges in a direction substantially perpendicular to the one direction, And a welding step of manufacturing a long-sided welded plate material that is long in the direction, and performing the rolling process in the longitudinal direction of the welded plate material to manufacture a metal thin plate having a target plate thickness.

That is, first, an intermediate thin plate is manufactured by drawing a predetermined plate-shaped metal material in one direction by forging, rolling, etc., and the rolling rate at this time is from the intermediate thin plate to the target metal thin plate. It is desirable that the rolling rate is about the same as that until the above is obtained.

Next, this intermediate thin plate is cut in a direction substantially perpendicular to one direction to manufacture a plurality of intermediate thin plate pieces, and the end edges of these intermediate thin plate pieces in the direction perpendicular to the one direction are butted and welded to each other. . When welding the intermediate thin plate piece, electron beam welding having a high energy density and a narrow width of the welded portion is desirable, but other welding means such as TIG welding may be adopted. In particular, in welding a high melting point metal such as tungsten, by using such electron beam welding, good weld joining can be performed. Since the edge portion of the intermediate thin plate piece has an irregular shape due to the stretching process, it is desirable to cut it off before the welding step or the cutting step.

Further, at the time of welding this intermediate thin plate piece, since the crystal grains are coarsened by recrystallization accompanying welding, a filler material for preventing the coarsening of the crystal grains, for example, when manufacturing a thin plate of tungsten, Mo (molybdenum), Ta (tantalum), Re (rhenium) that forms an alloy by forming a solid solution in tungsten
Etc. can be used, and further, a filler material for other purposes such as increasing welding strength can be used. In that case, since the composition of the welded portion changes, the welded portion is cut off as needed after the thin plate is manufactured.

The welded plate material obtained by welding the intermediate thin plate pieces in this way is then rolled in the longitudinal direction,
As described above, the metal of the welded portion is recrystallized and the crystal grains are coarsened, so that the workability is low, and cracks or cracks may occur during rolling depending on the metal material. When rolling such a metal material having particularly low workability, it is desirable to perform at least the first pass rolling after welding at a temperature higher than the recrystallization temperature. In this case, if the plate thickness of the welded plate material is too thin, the cooling and cooling due to contact with the rolling roll is significant, so when performing hot rolling, the plate thickness of the welded plate material, that is, the intermediate thin plate thickness is 0.4 mm or more. It is desirable to set to.

Further, particularly when manufacturing a thin metal sheet having a thin plate, by providing a winding roll before and after the rolling machine and rolling the welding plate material between both rolls while applying a strong tension, the rolling process is performed. For example, it is possible to manufacture a foil-shaped metal thin plate having a plate thickness of about 25 μm.

The method for producing a metal thin plate according to the present invention is particularly effective when producing a thin plate of tungsten or molybdenum to which the annealing treatment cannot be applied, or an alloy or the like using any one of them as a base material. However, it can be similarly applied to the case of manufacturing a thin plate from other metal materials.

EFFECTS OF THE INVENTION According to such a method for manufacturing a metal thin plate, the length in the longitudinal direction of the welded plate material to be rolled, that is, the dimension in the rolling direction becomes long, so that the metal thin plate having no orientation of the fiber structure is efficiently processed by the cross roll. Be able to manufacture. In particular,
In the case of a metal material having a high hardness, in which the rolling rate per pass is small and the rolling process needs to be repeated many times, the working efficiency can be greatly improved.

In addition, since a thin metal plate is manufactured by rolling a long welded plate material, it becomes possible to manufacture a long product such as a strip plate, and perform rolling by applying tension in the rolling direction. Since it is possible to manufacture an extremely thin metal thin plate, the restrictions on the length dimension and plate thickness of the metal thin plate to be manufactured are completely eliminated.

Further, since the thin metal plate obtained in this way has a long length, the amount of cutting at both ends in the length direction cut off after rolling is the same as that of conventional metal sheets having a short length. Compared with the case where both ends of the thin plate are cut off, the yield is significantly reduced, and the yield in manufacturing the thin metal plate is significantly improved. In addition, since the number of cut-off points is small, the time required for the cutting operation is greatly reduced, and in this sense, the working efficiency of the thin metal plate is improved.

Example Next, in order to further clarify the method of the present invention, an example in which the method of the present invention is applied to the production of a thin tungsten plate will be described in comparison with a conventional production method.

First, FIG. 1 is a perspective view showing a tungsten plate material 10 which is a material of a thin metal plate to be manufactured. This plate material 10 is made of pure tungsten (purity ≧ 99.9%) by cold isostatic pressing to obtain a plate thickness of 23 mm, a width of 105 mm, a length of 170 mm, and a density (compared to theoretical density of Tansugten 19.3 g / cm ³ The same shall apply hereinafter) 63% green compacts were stored in a hydrogen atmosphere at 1700 ° C
After pre-sintering, the current thickness is 20mm, width 9
3mm, width 150mm, density 92%. Two such plate-like materials 10 were prepared for the test described later. In addition,
As the plate-shaped material for manufacturing the thin metal plate of tungsten, in addition to such a sintered material, a molten material obtained by melt casting can be used.

Then, such two plate-shaped materials 10 are respectively stretch-processed in the longitudinal direction indicated by the arrow X in FIG. 2 to manufacture the intermediate thin plate 12. This stretching process is a plate-shaped material
While repeatedly heating 10 to 1700 ° C in a hydrogen atmosphere furnace, forging was performed by hammer forging in the atmosphere to obtain a plate thickness of 7 mm, a width of 105 mm, and a length of 375 mm, and then to 1500 ° C in a hydrogen atmosphere furnace. It was performed by repeatedly rolling and rolling with a two-high rolling mill. The dimensions of the intermediate thin plate 12 produced by this drawing process are as follows: plate thickness 2 mm, width
The length is 107 mm and the length is 1280 mm.

One of the two intermediate thin plates 12 produced in this way
The sheet is left as it is as the sample A, the other sheet is traversed at intervals of 115 mm in the longitudinal direction (X direction), and 10 pieces of the intermediate thin plate pieces 14 as shown in FIG. Only shown). This crossing is the cutting process.

Next, one of the ten pieces of the intermediate thin plate 14 thus obtained is left as the sample B, and the other nine pieces are subjected to the above-mentioned stretching process as shown in FIG. Both edge portions 16 in the Y direction perpendicular to the X direction, which are irregularly shaped, are cut off to form a cutting intermediate thin plate piece 18 having a width of 103 mm, and then, as shown in FIG. Y
The edges in the direction were butted against each other and welded. This step is a welding step, whereby a long welded plate material 20 that is long in the Y direction perpendicular to the stretching direction is obtained. The dimensions of this welded plate material 20 are a plate thickness of 2 mm, a width of 115 mm, and a length of 927 mm. Note that FIG. 5 shows a state in which three cutting intermediate thin plate pieces 18 are welded and joined, but the remaining six sheets are also welded and joined in succession to these.

Here, since the cutting intermediate thin plate piece 18 made of tungsten has a very high melting point, electron beam welding having a high energy density was adopted as the welding means in this example, and the welding was performed in the vacuum chamber. Further, in this welding and joining, if necessary, a filler material such as Mo, Ta, or Re is used to reduce the crystal grains of recrystallization accompanying welding, or a W-Re alloy is used to increase the welding strength. It is also possible to use a filler material such as.

Then, the welding plate material 20 manufactured in this manner is used as a sample C.
While repeatedly heating the sample A and the sample B in a hydrogen atmosphere furnace at 1500 to 1300 ° C., the sample A is in the X direction, and the samples B and C are in the Y direction by a four-high rolling mill. After rolling to a plate thickness of 0.5 mm, it was further rolled at the heating temperature of 1200 to 800 ° C. by the same rolling machine to a plate thickness of 0.3 mm. As a result, sample A has a plate thickness of 0.3.
mm, width 107 mm, length 8 m, sample B has a thickness of 0.3 mm, width of 115 mm and length of 0.
The sample C had a thickness of 0.3 mm, a width of 115 mm and a length of 6 m.

After that, the samples A and C were further rolled using a 20-high rolling machine with a work roll diameter of 10 mm at room temperature while applying tension (backward tension: forward tension ≈ 6: 4) in the rolling direction. Then, while rolling to a plate thickness of 0.25 mm, 0.20 mm, 0.15 mm, 0.10 mm, and 0.05 mm of plate thickness were sampled in the intermediate process. In addition, sample B cannot be applied with tension in the rolling direction due to its short length, so a 4-roll mill with a work roll diameter of 50 mm was used and the plate thickness was 0.15 without tension.
In addition to rolling to mm, sampling was performed at a plate thickness of 0.20 mm in the intermediate process. Figure 6 shows sample C (welded plate 20)
FIG. 3 is a diagram showing a thin metal plate 22 obtained by performing such rolling process on the above.

Then, with respect to each of the sampling pieces thus obtained, bending processing was performed up to 180 degrees along the X direction and the Y direction, and the occurrence state of cracks was measured. The results are shown in Table 1. In Table 1, 180 means that cracking did not occur even after bending up to 180 degrees, and numbers less than 180 indicate that angle. It means that a crack has occurred.

As is clear from Table 1, in the sample C according to the method of the present invention, the directionality of bending in the X direction and the Y direction is extremely higher than that in the sample A in which the stretching process is performed only in the X direction. You can see that it is getting smaller. This is the same for the sample B by the conventional cross roll, but in the case of the sample B, since it is not possible to carry out rolling while applying tension in the rolling direction with a short length, the plate thickness of the final product There is an inconvenience that the size is restricted.

Further, even when a thin plate having the same plate thickness is manufactured, since tungsten has a high hardness and a small rolling rate per pass, it is necessary to repeat the rolling process many times. Compared with the case of manufacturing a thin plate from the welded plate material (20), the working efficiency in directly manufacturing a thin plate from the short intermediate thin plate piece (14) is extremely low. Incidentally, when the sample B is rolled to produce a thin plate (conventional cross roll)
FIG. 7 shows the results of examining the actual rolling efficiency (kg / hour) in the case where the thin plate was manufactured by subjecting the sample C to the rolling process (the method of the present invention). In FIG. 7,
The mark indicates the case where the sample C was rolled, and the mark x indicates the case where the sample B was rolled.

In addition, the long welded plate material 20 is rolled to form a thin metal plate 22.
The long metal thin plate 22 such as a strip plate can be manufactured from the manufacturing process. Furthermore, since the metal thin plate 22 obtained in this way has a long length, the amount of cutting at both ends in the length direction (Y direction) cut off after rolling is directly rolled into a large number of intermediate thin plate pieces 14. Compared with the case where a metal thin plate is manufactured by processing, the amount is significantly reduced, the product yield is improved, and the time required for excision work is saved, and the processing efficiency is also improved in this respect.

As described above, one example of the method of the present invention and the test results have been described in detail, but these are merely specific examples, and the method of the present invention is variously modified based on the knowledge of those skilled in the art.
It can be implemented in an improved mode.

[Brief description of drawings]

FIG. 1 to FIG. 6 are views for explaining an embodiment in the case of manufacturing a tungsten thin plate according to the method of the present invention.
The figure is a perspective view showing a plate-shaped material that constitutes the material of the Tangsouten thin plate. FIG. 2 is a perspective view showing an intermediate thin plate obtained by stretching the plate-shaped material of FIG. FIG. 3 is a perspective view showing a plurality of intermediate thin plate pieces obtained by cutting the intermediate thin plate of FIG. FIG. 4 is a perspective view showing a state in which an edge portion of the intermediate thin plate piece of FIG. 3 is cut off. FIG. 5 is a perspective view showing a welded plate material obtained by welding and joining the cutting intermediate thin plate pieces of FIG. Sixth
The drawing is a front view showing a thin metal plate obtained by rolling the welded plate material of FIG. FIG. 7 is a graph showing the actual rolling efficiency in the case of producing a metal thin plate by the method of the present invention in comparison with a conventional cross roll. 10: Plate material, 12: Intermediate thin plate 14: Intermediate thin plate piece, 20: Welded plate material 22: Metal thin plate X: One direction Y: Direction perpendicular to one direction

Claims (7)

[Claims] 1. A sheet material is stretched in one direction to produce an intermediate thin plate, and then the intermediate thin sheet is rolled in a direction substantially perpendicular to the one direction to produce a metal thin plate having a predetermined thickness. A cutting step of producing a plurality of intermediate thin plate pieces by cutting the intermediate thin plate in a direction substantially perpendicular to the one direction; and a method of cutting the plurality of intermediate thin plate pieces in a direction substantially perpendicular to the one direction. And a welding step of manufacturing a long-long welded plate material in a direction perpendicular to each other by welding the edges to each other, and performing a rolling process in the longitudinal direction of the welded plate material to obtain a thin metal plate having a desired plate thickness. A method for producing a thin metal plate, characterized in that 2. The method for producing a thin metal plate according to claim 1, wherein the plate-shaped material is tungsten, molybdenum, or an alloy containing any one of them as a base material. 3. The method for manufacturing a thin metal plate according to claim 1, wherein the welding step is performed by electron beam welding. 4. The metal according to any one of claims 1 to 3, wherein the welding step is performed using a filler material that reduces the crystal grains of recrystallization accompanying welding. Method for manufacturing thin plate. 5. The method for producing a metal thin plate according to claim 1, wherein the rolling process includes hot rolling process. 6. The method for producing a metal thin plate according to claim 5, wherein the thickness of the intermediate thin plate is 0.4 mm or more. 7. The method for producing a thin metal plate according to claim 1, wherein the rolling is performed by applying tension in the longitudinal direction of the welded plate material.