JP2005305510A - Press die tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press die tool having excellent practical durability with respect to the shearing and bending which are performed repeatedly. <P>SOLUTION: In the press die tool to perform the shearing or bending by a lower die 2 and an upper die 1, a hard layer 8 having the Vickers hardness (HV) of ≥1,500 is provided at least as an outermost layer on an upper face A1 of the lower die and a lower face A2 of the upper die. A hard layer 5 may also be provided on side faces of the upper and lower dies. The maximum height of the surface roughness of the front and rear dies having the hard layer is preferably ≤8 μm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a press-type tool having a hard layer on its surface and excellent in durability. The press die tool of the present invention will be described in detail later, but a pair of upper and lower molds for bending used in a pair of upper and lower molds having a cutting edge used in a shearing process, for example, a scrap cutter, a press brake, etc. It refers to a pair of upper and lower molds provided with a mold and a curved blade used in a step of shaping a metal plate that has been previously bent into a predetermined shape (hereinafter referred to as a restoric step).

  Since a pair of upper and lower molds provided with a cutting blade or a curved blade used for pressing a metal plate is used in a mass production process, problems such as wear and seizure occur during long-term use. In addition, depending on the material to be processed, a large load is applied to the mold, which may cause defects or cracks. As countermeasures for these, lubrication and cooling are mainly performed using processing oil, but in response to demands such as improvement of the working environment and omission of the degreasing process, the process is shifting to dry or semi-dry processing.

  Most of the conventional techniques for improving the durability of tools are directed to cutting blades for cutting such as drills, milling cutters, cutting tools and chips. In the cutting tool, problems such as wear, seizure, adhesion, die squeeze, and chipping occur as in the case of the tool used for press working. The following methods are known as countermeasures against these problems of cutting tools.

  (1) A method of coating a hard film made of a carbide or nitride such as Ti, Al, or V on a tool such as steel or cemented carbide.

  (2) A method of providing a modified layer on the tool by diffusion treatment.

  (3) A method of coating a tool with a lubricious solid film including diamond-like carbon (hereinafter referred to as DLC).

  In addition, if these films are peeled off during processing, the effect cannot be obtained sufficiently. Therefore, technology for etching the base material to improve the adhesion between the base material and the film, the base material and the hard film A technique for providing an intermediate layer between them is known.

  For example, in Patent Document 1 (Japanese Patent Laid-Open No. 2003-305601), a hard coating made of carbide, nitride, or carbonitride nitride such as Ti, Al, Cr, V, Si, and B is applied to tool steel and cemented carbide. Adhesion is increased by coating through an intermediate layer made of Ti, Al carbide, nitride or carbonitride nitride, and wear and adhesion are reduced by coating a solid lubricating film on the outermost layer. It has been shown that long-time, high-speed cutting in dry or semi-dry is possible.

  The above technology is intended for plastic working jigs in general, but mainly for cutting blades for cutting such as drills and end mills, and the load is intermittent as in press working using a mold. In the case of using it as a tool that requires repeated operation, the effect has not been clarified. Although it is considered that the effect of the roughness of the tool surface having a strong correlation with the surface notch effect is large for the chipping of the tool, the above document does not describe the surface roughness.

  Patent Document 2 (Japanese Patent Laid-Open No. 10-287491) discloses a tool having excellent durability in which the roughness of the tool surface is adjusted to 0.1 to 2.5 μm with an average surface roughness Ra and then coated with DLC. Yes.

  However, the adjustment of the surface roughness is mainly made to improve the adhesion of the coating film, and in order to prevent the surface damage of the tool, it is not possible to obtain a sufficient effect only by controlling the average surface roughness. .

  Patent Document 3 (Japanese Patent Laid-Open No. 5-311439) discloses a mirror surface finish so that the maximum surface roughness Rz is 0.3 μm or less, and has an ion-implanted layer formed on the surface, thus providing excellent wear resistance. A mold for shearing is disclosed. It has been shown that by making the maximum height 0.3 μm or less, the tool surface is uniformly cured by ion implantation and the mold life is improved. However, durability in the above technique refers to wear resistance, and there is no mention of mold defects. The workpiece in the above technique is a very small member such as an electronic component contact. Finishing the maximum height of the surface roughness to 0.3 μm or less for a tool for processing a large part such as a member for an automobile is time-consuming and unrealistic due to high costs.

  The above technique has been applied to improve the durability of tools such as dies with cutting edges and tools for bending as well, such as press working, where the load is repeatedly applied repeatedly. It was.

  FIG. 3 is a diagram for explaining shearing by a mold having a cutting edge used in the shearing process. FIG. 3A is a longitudinal sectional view around the mold showing a state immediately before shearing, and FIG. 3B is a perspective view thereof. As shown in these drawings, the steel plate 3 as a workpiece is sheared by placing a workpiece, for example, a steel plate 3 on a lower mold 2 provided with a lower blade 6b. This is achieved by moving the upper mold 1 provided with the upper blade 6a downward while sandwiching the steel plate with the pad 4.

  In a mass production factory, such processing is repeated tens of thousands of times, resulting in wear and chipping on the cutting edge. Conventionally, as shown in FIG. 3, the hard layer, the modified layer, the lubricous solid film, etc. 5 are provided on the side surface B1 of the lower mold and the side surface B2 of the upper mold that face each other during processing. . However, since sufficient durability cannot be obtained only by such measures, a better measure has been desired.

JP 2003-305601 A Japanese Patent Laid-Open No. 10-287491 Japanese Patent Laid-Open No. 5-311439

  An object of the present invention is to provide a press-type tool having excellent practical durability against repeated shearing and bending. Practical durability means that the quality of the processed product is maintained even during long-time processing, as well as the fact that the tool is not easily damaged or worn. It means maintenance-free with about 30,000 shots (30,000 shearing or bending).

  The gist of the present invention resides in a press-type tool having excellent durability (1) to (3) below.

  (1) A press-type tool that performs shearing or bending using a lower die and an upper die, and has a Vickers hardness (HV) of 1500 or more as at least the outermost layer on the upper surface of the lower die and the lower surface of the upper die Press type tool with a hard layer.

  (2) The press die according to the above (1), wherein the maximum height (Rz) of each surface roughness of the lower mold upper surface and the upper mold lower surface before providing the hard layer and after providing the hard layer is 8 μm or less. tool.

(3) A press die tool that performs shearing or bending with a lower die and an upper die, and includes an upper surface of the lower die and a lower surface of the upper die, and a side surface and an upper die of the lower die that face each other during processing. A press die tool provided with a hard layer having a Vickers hardness (HV) of 1500 or more and a thickness of 5 μm or less as at least an outermost layer on each side of the mold.
The maximum height (Rz) of the surface roughness is in accordance with the provisions of Japanese Industrial Standard (JIS) B0601. A press tool is a pair of upper and lower molds having cutting edges, a pair of upper and lower molds for bending, or a pair of upper and lower molds for bending and shaping a pre-bent metal plate into a predetermined shape. A type. Further, when the cutting blade or the curved blade is not integral with the mold and the blade is attached to the mold, the lower surface and the upper surface of each blade are also encased in the lower surface and the upper surface of the mold.

  As a result of observing the wear and chipped state of the mold used for mass production and repeatedly conducting the durability test, the present inventors have obtained the following knowledge and completed the present invention.

  a) In a mold subjected to continuous shearing or bending by a press, damage due to defects or cracks on the upper surface or the lower surface of the mold is more often observed than wear of the side surface of the mold, which has been a concern in the past. Therefore, it is necessary to protect the upper and lower surfaces of the mold.

  b) The effect of improving the durability of the hard layer applied to the mold surface is higher than that of the upper surface of the lower mold and the upper mold, compared to the case where the hard layer is applied to the side surface of the lower mold and the side surface of the upper mold facing each other. It is much larger when applied to the lower surface (hereinafter also referred to as the opposing surface).

  c) Defects in the mold are generated starting from grinding wrinkles caused by machining that occur when the mold is manufactured. This is presumed to be because the grinding rod acts as a notch (notch) due to the load repeatedly applied to the tool surface, causing impact fracture or fatigue fracture. Therefore, it is essential to improve the durability of the tool by reducing the notch sensitivity of the grinding rod.

  d) The notch sensitivity of the grinding rod can be reduced by adjusting the maximum height of the mold surface roughness, and the maximum height can be allowed up to 8 μm. The “mold surface roughness” here means the surface roughness of the tool base material before providing the hard layer and the roughness of the tool surface after providing the hard layer.

  e) When a hard layer is provided on the upper surface of the lower mold and the lower surface of the upper mold, residual stress is generated in the film during the formation of the hard layer. This residual stress relieves the tensile stress that is generated by the impact load during use of the tool and acts to cleave the grinding surface of the tool surface.

  f) In order to improve the wear resistance of the mold and achieve maintenance free of 30,000 shots, the hardness of the hard layer needs to be Vickers hardness of 1500 or more.

  FIG. 1 shows an example of a mold provided with a cutting edge for external trim of the present invention used in a shearing process, and FIG. 1A is a longitudinal sectional view around the mold showing a state immediately before shearing a steel sheet. FIG. 1B is a perspective view thereof, and FIG. 1C is a perspective view of a mold in which a hard layer is also provided on the side surface of the mold.

  FIG. 2 is a longitudinal sectional view of the periphery of a mold showing an example of a mold provided with a bending blade for bending according to the present invention used for a press brake or the like and showing a state before bending. 2A is a longitudinal sectional view of a mold for bending the workpiece 3 at 90 degrees, and FIG. 3B shows a desired workpiece 3 that has been previously bent. It is a longitudinal cross-sectional view of the mold periphery provided with the curved blade used for the wrist-like process shape | molded in a shape.

  The present invention is directed to press-type tools used for shearing and bending as shown in FIGS. 1 to 3, and these tools are all in contact with a workpiece and shocking. Loaded and has the same problem with durability. Hereinafter, the description will be made based on a mold provided with a cutting edge for external trim used in these typical shearing processes, but the effects described below are also the same in a bending mold.

  As shown in FIG. 1B, the press tool of the present invention has a hard layer 8 having a Vickers hardness (HV) of 1500 or more as at least the outermost layer on the upper surface A1 of the lower mold 2 and the lower surface A2 of the upper mold 1. It has.

  FIG. 1 (c) shows a press tool according to another embodiment of the present invention, in which an upper surface A1 of the lower mold 2 and a lower surface A2 of the upper mold 1, and a side surface B1 and an upper mold of the lower mold facing each other during processing. On each side of the side surface B2 of the mold, hard layers 8 and 5 having a Vickers hardness (HV) of 1500 or more and a thickness of 5 μm or less are provided as at least the outermost layer.

  Hereinafter, the conditions defined in the present invention will be described in detail.

1. Hard layer:
The hard layer is applied to protect the tool surface. The hard layer is a layer whose surface is coated by a chemical vapor deposition method or a physical vapor deposition method, or a hard layer formed by diffusion treatment, sputtering, ion plating, or the like. Generally, a chemical vapor deposition method is preferred because a hard coating by a physical vapor deposition method has poor adhesion to a base material. Examples of the hard coating include carbide and nitride coatings such as Ti, Al, and V.

  As the hard layer, DLC having excellent lubricity while being hard is suitable. Since the effect cannot be obtained if the coating is peeled off due to impact during processing, the coating is required to have adhesion with a base material that can withstand the impact during processing. When the film treatment is performed by the vapor deposition method, it is preferable to perform the vapor deposition treatment after performing a pretreatment such as sputtering or peening in order to improve the adhesion.

  In conventional shearing work, it is recognized that it is important to prevent the work material from biting during shearing and wear due to friction with the work material when the scum rises. Attempts were made to ensure sex.

  However, when processing a high-strength material such as a high-tensile steel plate, the opposing surfaces (upper surface and lower surface) of the mold that come into contact with the material prior to the wear of the mold side surface and are subjected to shock loads This causes the problem of defects. The cause of the defect is an impact load repeatedly applied to the opposing surface of the mold. Therefore, in order to prevent defects and improve durability, it is necessary to reduce the load sensitivity of the opposing surface of the mold. As a countermeasure for that, it is conceivable to first reduce the maximum height of the surface roughness of the facing surface to suppress the notch effect due to the minute unevenness. However, this alone can suppress the progress of cracks up to defects, but cannot prevent the occurrence of cracks.

  Therefore, in the present invention, a hard layer that has been used for preventing wear on the side surface of the mold is conventionally applied to the opposing surface of the mold, and cracks in the mold base material are suppressed by its strength. Since the compressive stress remains in the hard layer, and the compressive residual stress acts to eliminate the tensile stress that generates and propagates cracks, it suppresses the generation and propagation of cracks on the opposing surface of the mold. . Further, the hard layer has a small coefficient of friction with the workpiece. As a result, the stress generated by sliding with the workpiece during processing and applied to the mold is reduced, and the effect of suppressing the stress amplitude of the repeated load can be expected. In order to expect this effect, it is desirable to coat DLC which has a large effect on improving the slidability. Of course, as in the case of coating the side surfaces of the mold, the effect of suppressing wear is exhibited.

  The area on which the hard layer is provided is not particularly limited, but it is effective to provide the hard layer at a site where an impact load or concentrated load is applied during processing from the viewpoint of improving fracture resistance. Specifically, in the case of a cutting edge tool, it is sufficient to apply about 15 mm from the edge of the cutting edge. However, most cutting tools are used for relief processing leaving about 15 to 20 mm from the edge of the cutting edge, and masking only increases man-hours and has no particular merit. A hard layer is provided on the entire surface of the opposite surface. The same applies to the side surface, and generally, the relief processing is performed leaving about 10 mm from the edge of the cutting edge, and as a result, the entire side surface is provided. It is not necessary to perform masking especially for a tool that does not perform escape processing.

2. Hard film hardness:
In order to achieve the purpose of improving the durability of the tool, the hard layer requires a certain level of hardness. In cutting, the tool surface hardness is required to be approximately 4 times or more that of the workpiece. In general, the hardness of iron-based materials is Vickers hardness, which is about 1/3 of the tensile strength (in MPa). In consideration of applying to a 980 MPa super high strength high strength steel plate having the highest tensile strength among the target workpieces in the present invention, the film hardness of the outermost layer in contact with the workpiece is 1500 or more in terms of Vickers hardness (HV). It was. More desirable is 2000 or more.

3. Hard layer thickness:
The thickness of the hard layer is not particularly limited, but is preferably 1 μm or more from the viewpoint of ensuring wear resistance. On the other hand, if the hard layer is too thick, peeling or defects inside the film are likely to occur, and it is desirable that the thickness be 10 μm or less.

  FIG. 4 is a diagram showing a cutting edge ridge line state when the hard layer is made too thick. FIG. 4A is a state where the arc (R) of the cutting edge that occurs when the hard layer is made thicker, FIG. (B) shows a state in which the hard layer is thickened at the edge portion of the blade edge and blistering occurs. If the hard layer is made too thick, the cutting edge becomes round at the edge of the cutting edge as shown in FIG. In addition, depending on the method of generating the hard layer, the film may become thick locally as shown in FIG. 4B, resulting in blistering, cutting edge sharpness, and stress concentration in the blistered portion. There may be a deficit. Therefore, it is preferable to make the thickness so that blisters and R do not become large. A preferable thickness of the hard layer is 5 μm or less.

  When the thickness of the hard layer is 5 μm or less, there is not much concern as described above. Therefore, a hard layer may be formed on the side surface, which has an effect of improving wear resistance. When the hard layer becomes thick as described above and the cutting edge R becomes large or blisters increase, it is preferable to remove the blisters and R portion by polishing or machining.

4). Mold surface roughness:
It is common knowledge that surface roughness affects fatigue life, but various types of surface roughness are defined. For example, the arithmetic average height Ra and the maximum height Rz specified in JIS B0601. The maximum height Rz has the strongest correlation with the fatigue life of the tool. In order to increase the durability of the tool, the maximum height Rz of the tool surface roughness is never small. It is known that the fatigue life becomes infinite when the maximum height Rz falls below a certain value “Rz-lim”. Therefore, if the tool surface is finished finer than Rz-lim, theoretically, tool failure due to fatigue will not occur. However, Rz-lim here is not always a practically realizable value, and is generally considered to be a value that is so small that it cannot be achieved.

  If the maximum height Rz is about 8 μm, it can be finished without special processing. In addition, when a solid lubricant hard coating was applied to a tool base material having an Rz of 8 μm by a durability test in a laboratory, the durability was practically sufficient and the maximum height of the surface roughness was reduced. It was confirmed that the durability was further improved as time went on. Moreover, when a hard layer was produced | generated on the tool base material surface, almost no change was seen in the original base material and Rz.

  In view of the above, the maximum surface height Rz of a preferable press mold is 8 μm or less, and more preferably 5 μm or less. It is preferable that the surface after the generation of the hard layer is similarly managed. Of course, it is particularly desirable to further polish the hard layer surface by diamond wrapping after coating to reduce the maximum height.

5). Mold base material:
As the mold base material, it is recommended to use ferrous alloys, especially hardened and tempered steel whose hardness and toughness can be adjusted by heat treatment, and matrix high-speed (high toughness, high-speed tool steel) steel with high toughness. . In the case where the material to be sheared has a low strength such as a thin aluminum alloy plate, casting or flame quenching steel may be used as the mold base material.

  The deformation resistance and wear resistance of a mold base material are proportional to its hardness. Higher hardness is desirable for use as a press-type tool exposed to large loads and surface pressures. On the other hand, toughness that affects fracture resistance is generally inversely proportional to hardness. Is not desirable. In the present invention, since the surface hardness is ensured by coating, the hardness of the base material is sufficient if it does not cause plastic deformation due to the load during processing.

  Quenched and tempered steel (JIS SKD11), which is widely used as a press die tool, has a 0.2% compressive proof stress of 1500 MPa or more when the Rockwell hardness (HRC) is 45, and has the highest strength covered in the present invention. It is sufficient for 980MPa high-grade high-strength steel sheets that are processed materials. For this reason, it is recommended that the base material hardness of the press working tool according to the present invention be HRC45 or higher. Of course, if the deformation of the base material is small, the burden on the film is reduced and effective in preventing the peeling of the film.

  On the other hand, increasing the base material hardness generally reduces toughness, which is undesirable from the viewpoint of fracture resistance. Although it is difficult to accurately express toughness by numerical values, in general, Charpy impact energy absorption value (hereinafter abbreviated as Charpy value) is often used as an indicator of toughness. Of course, it is desirable that the tool base material also has a high Charpy value. However, since the Charpy value is measured by a destructive test, the Charpy value cannot be measured for each manufactured tool. For the same tool steel, the Charpy value and hardness have an inverse correlation, and the approximate toughness can be estimated by measuring the hardness.

  In the case of JIS SKD11, it is empirically known that if it is HRC60 or less, the toughness will not be drastically reduced. When using this steel, select the appropriate quenching and tempering conditions and make it HRC60 or less. It is recommended. In addition, it is necessary to determine the hardness of other steel materials in order to ensure toughness in consideration of the balance between toughness and hardness. In addition, it is desirable to keep the cutting edge ridge line before coating as sharp as possible. Further, in order to reduce the thermal distortion of the base material during the film coating treatment, it is desirable that the base material is tempered at a high temperature of 500 ° C. or higher. When correction is required from the original shape due to a design change or the like, the shape may be changed by overlaying. In this case, it is necessary to select a material for the build-up as close as possible to the tool base material and satisfy the specified hardness by appropriate heat treatment.

  The press tool of the present invention can be used when processing iron-based alloy materials (including stainless steel), pure aluminum and aluminum alloy materials, pure copper and copper alloy materials, magnesium alloy materials, and titanium alloy materials. In particular, when it is used for processing a high-strength material such as high-tensile steel and a material that easily adheres to a tool such as an aluminum alloy, the effect is remarkably exhibited. It is also effective when trimming a material other than the above, for example, a resin material such as acrylic or a printed circuit board.

  Although it is clear that tool wear is less likely to occur when the coefficient of friction between the tool and the workpiece is low, the effect of reducing the load applied to the tool during machining is also recognized, which is thought to contribute to prevention of chipping. It is done. When coating is not performed with normal tool steel, the friction coefficient with iron-based materials with rust-preventing oil attached is about 0.12, so lubrication is especially performed after surface modification by coating. Even if not, it is desired to be smaller than this value. More desirable is 0.1 or less. When DLC is coated, the friction coefficient is remarkably reduced, and a very good effect is obtained in any of wear resistance, adhesion resistance, and fracture resistance.

  In order to evaluate the durability of a mold provided with a hard layer, a blade provided with a hard layer by changing the type of hard layer, the surface of the mold provided with the hard layer, the thickness of the hard layer, and the mold surface roughness A durability test was performed in which a 980 MPa class high-tensile steel plate was continuously cut and sheared. Table 1 shows the test conditions.

  FIG. 5 is a longitudinal sectional view showing an outline of a 20-ton crank press used in the test. The lower mold 11 is fixed, and the upper mold 10 repeats vertical movement by an electric crank. A hoop material 12 to be processed is continuously fed onto the lower mold 11 by a feeding device 14 and sheared when the upper mold is lowered. At the time of cutting, the workpiece is pressed by the urethane pad 15, and the hoop is sandwiched between the pad and the lower mold.

  FIG. 6 shows the shape of the cutting edge. The shape of the test blade used in the durability test is the same for both the upper blade and the lower blade. The cutting blade is fixed to the mold by a bolt passed through the bolt hole 15. In the figure, L indicates the position of the blade used for cutting.

  Using the above-mentioned apparatus, the durability test was performed by sequentially feeding the hoop materials and continuously shearing them. In addition to the presence or absence of defects, cracks, and film peeling by visual and microscopic observation, the cutting edge durability is also evaluated for the burr height of the work material in order to add an evaluation related to the sharpness, and the burr height is 0.2 mm. The cutting edge was considered to have reached the end of its life when exceeded.

  The tool steel used as the base material was all SKD11, the hardness (HRC) was unified to 58, and the hard layer was a DLC and VC hard layer. DLC is a solid lubricating hard coating that can obtain a very low coefficient of friction while having high hardness.

By plasma CVD in this embodiment, methane as a raw material gas, a small amount of silicon to improve the adhesion between the base material, SP ³ bond with the same carbon as the natural diamond to a tool steel surface as a cutting blade base material And an amorphous structure coating containing SP ² bonds of carbon same as graphite and bonds of hydrogen and silicon. The processing temperature is 500 ° C. and the film thickness is 3 μm. Further, the VC hard layer was produced by diffusing and generating a vanadium carbide hard layer on the tool surface by a molten salt immersion method (so-called TD process). The processing temperature was 1000 ° C. and the thickness of the hard layer was 8 μm. For tools with VC hard layers, a hard layer is created on the entire surface of the tool, and a die with the hard layer remaining on the die facing surface is prepared while grinding the side surface to ensure the sharpness of the cutting edge. did.

  For comparison, a mold was prepared by masking the opposite surface of the mold as conventionally performed and providing a hard layer only on the side surface. Table 2 shows test conditions and durability test results. It can be seen that the tool corresponding to the embodiment of the present invention has a durability three times or more that of the conventional product.

  ADVANTAGE OF THE INVENTION According to this invention, the defect | deletion of a press type tool, adhesion, and abrasion can be suppressed, and it becomes possible to process into a product of stable quality, without performing special maintenance over a long period of time.

It is the longitudinal cross-sectional view and perspective view of the press type tool of this invention. It is a longitudinal cross-sectional view of the other press type tool of this invention. It is the longitudinal cross-sectional view and perspective view of the conventional press type tool. It is a figure which shows the abnormal blade state by a thick hard layer. It is a longitudinal cross-sectional view which shows the outline of a durability test apparatus. It is a perspective view of the cutting blade used in the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 .... Upper die 2 .... Lower die 3 .... Work material 4 .... Pad 5, 8 ... Hard layer 6a and 6b ... Cutting blade
A1 ... the upper surface of the lower mold
A2 ・ ・ ・ ・ Lower surface of upper mold
B1 ・ ・ ・ ・ Side side of lower mold
B2 ・ ・ ・ ・ Side side of upper mold

Claims (3)

  A press tool that performs shearing or bending with a lower mold and an upper mold, and has a hard layer with a Vickers hardness (HV) of 1500 or more as at least the outermost layer on the upper surface of the lower mold and the lower surface of the upper mold A press-type tool characterized by comprising:   2. The press tool according to claim 1, wherein the maximum height (Rz) of each surface roughness of the upper surface of the lower die and the lower surface of the upper die before and after providing the hard layer is 8 μm or less. A press tool that performs shearing or bending by means of a lower mold and an upper mold, the upper surface of the lower mold and the lower surface of the upper mold, and the side surfaces of the lower mold and the upper mold that face each other during processing A press-type tool comprising a hard layer having a Vickers hardness (HV) of 1500 or more and a thickness of 5 μm or less as an outermost layer at least on each surface.

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