JP4436312B2 - Metal material pressing method - Google Patents

Description

  The present invention relates to a metal material pressing method. More specifically, the present invention relates to a method of processing a metal material using a surface-treated mold in a state where lubricating oil is supplied between the metal material and the mold.

  Various methods such as punching, half punching, bending, and burring are known as metal material pressing methods. When such a metal material is pressed, lubricating oil is supplied between the metal material (material to be processed) and the mold. Thereby, the generation of frictional heat between the metal material and the mold is prevented, and the occurrence of burrs and the like on the processed surface is prevented. Further, by supplying the lubricating oil, the processing accuracy of the processed product is improved, and the life of the die such as a die or a punch is extended.

  In many cases, a chlorinated lubricating oil is used as a lubricating oil used in pressing a metal material. However, it has been pointed out that a chlorine-based lubricating oil has a problem that a chlorine-based additive component contained therein is decomposed during processing or over time to rust a material to be processed or a mold. In addition, chlorinated lubricants have been pointed out as problems such as generation of harmful substances during incineration and corrosion / damage of incinerators. Accordingly, there is a demand for a lubricating oil for press working that does not contain a chlorine-based substance and has seizure resistance and lubricating performance equivalent to or higher than that of a chlorine-based lubricating oil.

Therefore, as a lubricating oil not containing a chlorine-based additive, for example, one described in Patent Document 1 is known. However, the lubricating oil described in Patent Document 1 is a lubricating oil for cutting work, and does not have sufficient seizure resistance and lubricating performance, and is used as a lubricating oil for press working of metal materials, particularly for precision shearing. In order to achieve this, the performance is insufficient.
Patent Documents 2 and 3 disclose a cutting oil composition containing an overbased metal sulfonate, a sulfur-based extreme pressure agent, and the like. However, these lubricating oils exhibit good lubricating performance in general metal processing, but there is a problem that sufficient lubricating performance cannot be exhibited in press processing with high difficulty such as precision shearing.

JP 2002-155293 A Japanese Patent No. 2641203 JP-A-8-20790

  Therefore, the present invention can further reduce the friction between the metal material and the mold, improve the processing accuracy of the press-processed product, and extend the life of the mold compared to the conventional one. It is an object of the present invention to provide a method of pressing a metal material that can be achieved.

The inventors of the present invention focused on both the lubricating oil used in the press working of the metal material and the surface treatment method of the mold used in combination therewith. As a result, when a lubricating oil having a specific composition and a mold that has been surface-treated under a specific condition are used, it is possible to improve the processing accuracy of the processed product as compared with the prior art. The inventors have found that it is possible to extend the life of the mold, and have completed the following invention.
A first invention is a method of pressing a metal material using a surface-treated mold in a state in which lubricating oil is supplied between the metal material and the mold, and the surface treatment includes: After fine particles made of high-speed tool steel having an average particle size of 30 μm or more and 80 μm or less are sprayed on the surface of the mold at an injection speed of 130 m / s or more and 170 m / s or less, a ceramic material having an average particle size of 40 μm or more and 70 μm or less is formed. This is a treatment in which fine particles are sprayed onto the surface of a mold at an injection speed of 130 m / s or more and 170 m / s or less. The lubricating oil comprises a lubricating base oil, a sulfur-based extreme pressure agent, an organic zinc compound, and a calcium-based material. A lubricating oil comprising an additive and an ester compound, wherein the sulfur-based extreme pressure agent has a sulfur content of 5% by weight or more and the organic zinc compound has a zinc content of 0.5% by weight. Above The calcium additive is a lubricating oil having a calcium content of 0.5% by weight or more and a content of the ester compound of 1.0% by weight or more (“% by weight” is based on the total amount of the lubricating oil). And a metal material press working method.
According to a second invention, in the first invention, the metal material is press-worked by pressing the metal material on the surface of the die that has been surface-treated using a die that has been further subjected to titanium nitride coating treatment. Is the method.

  According to the present invention, in the press working of a metal material, it is possible to further reduce the friction between the metal material and the mold, to further improve the processing accuracy of the pressed product, It is possible to extend the service life.

The present invention is a method of pressing a metal material using a surface-treated mold in a state in which lubricating oil is supplied between the metal material and the mold, and the surface treatment includes average grains Fine particles made of a high-speed tool steel having a diameter of 30 μm or more and 80 μm or less are sprayed on the mold surface at an injection speed of 130 m / s or more and 170 m / s or less, and then fine particles made of a ceramic material having an average particle size of 40 μm or more and 70 μm or less. , 130 m / s or more and 170 m / s or less spraying the surface of the mold, the lubricating oil is a lubricant base oil, a sulfur-based extreme pressure agent, an organic zinc compound, and a calcium-based additive And an ester compound, wherein the sulfur-based extreme pressure agent has a sulfur content of 5% by weight or more, and the organozinc compound has a zinc content of 0.5% by weight or more. Yes The calcium additive is a lubricating oil having a calcium content of 0.5% by weight or more and a content of the ester compound of 1.0% by weight or more (“% by weight” is based on the total amount of the lubricating oil). ), A metal material press working method.
Below, the "lubricating oil" used for this invention is demonstrated first, and the surface treatment method of a metal mold | die is demonstrated after that.

[About lubricating oil]
The lubricating oil used in the present invention comprises (a) a sulfur-based extreme pressure agent, (b) an organic zinc compound, (c) a calcium-based additive, and (d) an ester compound. It is a lubricating oil for press working of metallic materials formed by blending. The lubricating oil used in the present invention does not contain a chlorine-based additive, and has high seizure resistance and lubricating performance equal to or higher than that of the chlorine-based lubricating oil.

In the lubricating oil according to the present invention, at least one selected from mineral oil, synthetic oil, and fat is used as the lubricating base oil. These mineral oils, synthetic oils, and fats and oils are not particularly limited as long as they are generally used as base oils for metal processing oils, but the kinematic viscosity at 40 ° C. is 1 mm ² / s or more. is preferably one in 1000 mm ² / s or less in the range, it is more preferably in the following range 5 mm ² / s or more 100 mm ² / s.

There are various types of such mineral oils, synthetic oils, and fats and oils, and they may be appropriately selected according to the use.
As mineral oil, the mineral oil refine | purified using a conventional method in the lubricating oil manufacturing process of a petroleum refinery industry can be used, for example. More specifically, for example, a lubricating oil fraction obtained by subjecting crude oil to atmospheric distillation and vacuum distillation is subjected to solvent removal, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, A purified product obtained by performing one or more treatments such as sulfuric acid washing and clay treatment.

  Examples of the synthetic oil include poly α-olefin, α-olefin copolymer, polybutene, alkylbenzene, polyoxyalkylene glycol, polyoxyalkylene glycol ether, and silicone oil.

  Specific examples of fats and oils include beef tallow, lard, soybean oil, rapeseed oil, rice bran oil, coconut oil, palm oil, palm kernel oil, and hydrides thereof.

  In the lubricating oil according to the present invention, only one of the above base oils may be used alone, or two or more base oils may be mixed and used.

  Next, four components blended in the lubricating base oil, that is, (a) a sulfur-based extreme pressure agent, (b) an organic zinc compound, (c) a calcium-based additive, and (d) an ester compound are described. To do.

(A) About sulfur type extreme pressure agent As a sulfur type extreme pressure agent, what has a sulfur atom and can exhibit an extreme pressure effect can be used. Specific examples of the sulfur-based extreme pressure agent include sulfurized fats and oils, sulfurized fatty acids, sulfurized esters, sulfurized olefins, polysulfides, thiocarbamates, and sulfurized mineral oils. Here, sulfurized fats and oils are obtained by reacting sulfur with fats and oils (lard oil, whale oil, vegetable oil, fish oil, etc.). Specific examples thereof include sulfurized lard, sulfurized rapeseed oil, sulfurized castor oil, and sulfurized soybean oil. Examples of the sulfurized fatty acid include sulfurized oleic acid, and examples of the sulfurized ester include sulfurized methyl oleate and sulfurized rice bran fatty acid octyl.

  The sulfurized olefin is obtained by reacting an olefin having 2 to 15 carbon atoms or a dimer or tetramer thereof with a sulfurizing agent such as sulfur or sulfur chloride.

  Specific examples of the polysulfides include dibenzyl polysulfide, di-tert-nonyl polysulfide, didodecyl polysulfide, di-tert-butyl polysulfide, dioctyl polysulfide, diphenyl polysulfide, and dicyclohexyl polysulfide.

  Specific examples of thiocarbamates include zinc dithiocarbamate, dilauryl thiodipropionate, distearyl thiodipropionate, and the like.

  Sulfided mineral oil refers to one obtained by dissolving elemental sulfur in mineral oil. The mineral oil that dissolves the elemental sulfur is not particularly limited, and for example, the mineral oil base oil exemplified in the description of the base oil can be used.

  In the present invention, the component (a) may be used singly or in combination of two or more. The sulfur content is preferably in the range of 1% by weight to 50% by weight, more preferably 5% by weight to 30% by weight, based on the total amount of the lubricating oil. If the amount is less than this range, the lubrication performance may not be maintained. If the amount is more than this range, the effect corresponding to the blending amount cannot be improved. The “sulfur content” herein refers to the content of sulfur atoms in the component (a), and can be obtained by calculation based on the atomic weight of sulfur.

(B) About an organic zinc compound As a preferable thing of an organic zinc compound, dialkyl dithiophosphate zinc (henceforth ZnDTP) and dialkyl dithiocarbamate zinc (henceforth ZnDTC) can be mentioned. The alkyl groups of ZnDTP and ZnDTC may be the same or different. That is, in the structural formula of ZnDTP, two alkyl groups are bonded to the phosphorus atom via an oxygen atom, and these alkyl groups may be the same or different. In the structural formula of ZnDTC, two alkyl groups are bonded to the nitrogen atom, but these alkyl groups may be the same or different. The alkyl group of ZnDTP and ZnDTC is preferably an alkyl group having 3 or more carbon atoms or an aryl group.

  In the present invention, the component (b) may be used singly or in combination of two or more. Further, the zinc content is preferably 0.01% by weight or more and 10% by weight or less, more preferably 0.5% by weight or more and 5% by weight or less, based on the total amount of the lubricating oil. If the amount is less than this range, the lubrication performance may not be maintained. If the amount is more than this range, the effect corresponding to the blending amount cannot be improved. Here, the “zinc content” is the content of zinc atoms in the component (b), and can be obtained by calculation based on the atomic weight of zinc.

(C) Calcium-based additive Preferable calcium-based additives include calcium sulfonate, calcium salicylate, and calcium phenate. In particular, calcium sulfonate is preferable from the viewpoint of kinematic viscosity and price. More preferably, it is a basic calcium sulfonate. More preferably, it is a basic calcium sulfonate having a base number of 300 mgKOH / g or more.

  In the present invention, the component (c) may be used singly or in combination of two or more. The calcium content is preferably in the range of 0.01 wt% to 10 wt%, more preferably 0.5 wt% to 5 wt%, based on the total amount of the lubricating oil. If the amount is less than this range, the lubrication performance may not be maintained. If the amount is more than this range, the effect corresponding to the blending amount cannot be improved. The “calcium content” here is the content of calcium atoms in the component (c), and can be obtained by calculation based on the atomic weight of calcium.

(D) Ester compound Preferred examples of the ester compound include a polyol ester and a complex ester. Only 1 type may be mix | blended with respect to lubricating base oil, and 2 or more types may be mix | blended.
The polyol ester is a polyol ester of an aliphatic polyhydric alcohol and a linear or branched fatty acid. Examples of aliphatic polyhydric alcohols that form polyol esters include neopentyl glycol, trimethylol propane, ditrimethylol propane, trimethylol ethane, ditrimethylol ethane, pentaerythritol, dipentaerythritol, and tripentaerythritol. Can do. In addition, partial esters of the above aliphatic polyhydric alcohols and linear or branched fatty acids can also be used.
The complex ester is a complex ester of an aliphatic polyhydric alcohol, a linear or branched fatty acid, and a linear or branched aliphatic dibasic acid. Examples of the aliphatic polyhydric alcohol component include trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol, and the like. Examples of the fatty acid component include aliphatic carboxylic acids such as heptadecyl acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, and lignoceric acid. Examples of dibasic acids include succinic acid, adipic acid, pemelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, carboxyoctadecanoic acid, carboxymethyloctadecanoic acid, docosanedioic acid and the like. Can do.

Ester compound, kinematic viscosity is preferable in the range of 100 mm ² / s or more 10000 mm ² / s, which is in the range of 1000 mm ² / s or more 5000 mm ² / s and more preferably at 100 ° C..
The content of the ester compound is preferably 0.5% by weight or more and 40% by weight or less based on the total amount of the lubricating oil. More preferably, it is 1.0 wt% or more and 20 wt% or less. If the content of the ester compound is too much less than this range, the seizure resistance tends to be lowered. If it is more than this range, the lubricating oil becomes highly viscous and the handleability deteriorates.

  The lubricating oil according to the present invention can be obtained by blending the above components (a) to (d) with the lubricating base oil, but the purpose of the present invention is to maintain the basic performance as a pressing oil. Various known additives and the like can be appropriately blended within a range that does not inhibit the above.

  Examples of the various known additives include rust preventives, antioxidants, anticorrosives, colorants, antifoaming agents, and fragrances. As the rust preventive agent, calcium-based rust preventive agent, barium-based rust preventive agent, wax-based rust preventive agent and the like, as the antioxidant, amine-based compound, phenolic compound and the like, as the anticorrosive agent, Benzotriazole, tolyltriazole, mercaptobenzothiazole and the like can be appropriately added as necessary. As the colorant, a dye or a pigment can be used.

  In the present invention, a gravity blasting device may be used as the device for spraying the fine particles on the surface of the mold.

In the present invention, the fine particles sprayed onto the surface of the mold are (A) substantially spherical fine particles made of high-speed tool steel (high speed) having an average particle size of 30 μm or more and 80 μm or less, and (B) an average particle size of 40 μm or more. Two types of substantially spherical fine particles made of a ceramic material of 70 μm or less are used. Here, the average particle diameter is a diameter by which the weight of the powder is divided into two when divided by a sieve, that is, a median diameter (d50).
The fine particles made of the (A) high-speed tool steel are fine particles made of a high-speed tool steel corresponding to SKH in JIS standards, and it is preferable to use particles having a hardness higher than the hardness of the mold to be sprayed.
The fine particles made of the ceramic material (B) are fine particles made of a material generally called ceramics, and it is preferable to use particles having a hardness higher than the hardness of the mold to be sprayed.

  By applying surface treatment to the surface of the mold, rapid heating and rapid cooling above the A3 transformation point are repeated on the surface of the mold, so that effects such as surface work hardening and increased fatigue strength due to the occurrence of compressive residual stress are obtained. Can be obtained at the same time. In addition, the hardening method itself of the metal surface by such a surface treatment is a technique already known by Japanese Patent Publication No. 2-17607.

  Further, by applying a surface treatment to the surface of the mold, an infinite number of fine concave portions are formed on the surface of the mold. This concave portion is a fine concave portion, and the concave portion functions as an “oil reservoir” for storing lubricating oil. As a result, when the metal material is pressed by a mold, the lubricating oil is easily held on the surface of the mold, so that oil shortage is prevented and friction on the surface of the mold is remarkably reduced. . In order to further reduce the friction on the surface of the mold, it is preferable to use fine particles having a spherical shape or a substantially spherical shape. When spherical fine particles are used, a concave portion having an arc-shaped cross section is formed on the surface of the mold. As a result, the surface tension of the lubricating oil tends to act, and the lubricating oil is applied to the surface of the mold. It is because it becomes easier to hold.

[Pressing method for metal materials]
The first feature of the metal material pressing method according to the present invention is to use the “lubricating oil” described above, and to use a die that has been subjected to the “surface treatment” described above. Is the second feature. That is, by combining the “lubricating oil” having a specific composition described above with the “surface treatment” under a specific condition described above, an effect superior to the case where each of them is carried out alone is obtained. Obtainable.

  After surface treatment is performed on the surface of the mold, the surface hardness of the mold is improved by performing titanium nitride coating treatment (TiN coating treatment) on the surface of the mold. Thereby, it is possible to extend the service life of the mold. The titanium nitride coating method is not particularly limited, and various known coating methods can be used. For example, a titanium nitride coating process by a PVD method (physical vapor deposition method) can be performed.

  The metal material press working method according to the present invention exhibits particularly excellent effects when applied to press working such as shearing such as punching and drilling and fine blanking (FB processing).

The metal material pressing method according to the present invention can be applied to any metal material. For example, the present invention can be used to press stainless steel, alloy steel, carbon steel, aluminum alloy and the like. The present invention exhibits an excellent effect particularly on carbon steel and alloy steel.

  Moreover, since the lubricating oil demonstrated above used for this invention does not contain a chlorine component, the problem of the rusting of a product or a metal mold | die can be avoided. The lubricating oil used in the present invention can be used without being limited to the type of metal that is the work material. For example, it can be used for stainless steel, alloy steel, carbon steel, aluminum alloy and the like. Of these, the lubricating oil used in the present invention exhibits an excellent effect particularly on carbon steel and alloy steel.

  According to the metal material pressing method of the present invention, the metal material pressing accuracy is improved. The method for supplying the lubricating oil is not particularly limited, and for example, a method such as application to the surface of the metal material by a roller or application to the surface of the metal material by spraying can be employed. Or you may apply | coat lubricating oil with respect to the surface of a metal mold | die instead of the surface of the metal material which is a workpiece material. By supplying lubricating oil between the metal material and the mold, it is possible to prevent the mold from being rusted and damaged, so that the service life of the mold can be extended. Further, since the friction between the metal material and the mold can be reduced, it is possible to prevent the occurrence of burrs and the like on the press-worked surface and improve the press work accuracy of the metal material.

  Specific examples of the metal material pressing method according to the present invention will be described below. The present invention is not limited to the following examples.

First, lubricating oils 1 to 8 having the compositions shown in Table 1 were prepared using the following base oil and various additive components.
(Base oil)
Base oil 1: paraffinic mineral oil (kinematic viscosity at 40 ° C .: 450 mm ² / s)
Base oil 2: Naphthenic mineral oil (kinematic viscosity at 40 ° C .: 46 mm ² / s)
Base oil 3: paraffinic mineral oil (kinematic viscosity at 40 ° C .: 10 mm ² / s)
(A) Component a1: Polysulfide (Sulfur content: 37% by weight)
a2: Polysulfide (sulfur content: 32% by weight)
a3: Sulfurized oil (sulfur content: 15% by weight)
a4: Sulfurized oil and fat (sulfur content: 11% by weight)
(B) Component b1: ZnDTP (Zinc content: 9% by weight Sulfur content: 16% by mass)
b2: ZnDTP (zinc content: 5% by weight, sulfur content: 11% by mass)
b3: ZnDTP (zinc content: 9% by weight, sulfur content: 15% by weight)
(C) component c1: calcium sulfonate (calcium content: 15% by weight)
(D) Component d1: Polyol ester and / or complex ester (other components)
e1: Chlorinated paraffin (chlorine content: 50% by weight)
e2: Vegetable oil and fat e3: Synthetic oil

About the lubricating oils 1-8 prepared with the composition shown in Table 1, performance evaluation was performed using the following apparatuses and methods.
(Evaluation test equipment)
Press machine: AIDA Link press VL-6000 (Production speed: 70 spm)
Material feed: 23.5mm
Work material: SPH440 (plate width: 70 mm, plate thickness: 4.6 mm)
Lubricating oil supply method: Supply uniformly to the surface of the work material with a resin roll Punch 1: SKD11
Punch 2: SKD11 + TiN coating Dies: SKD11

(Evaluation methods)
Lubricating oils 1 to 8 prepared with the composition shown in Table 1 are uniformly supplied to the surface of the material to be processed by a resin roll, and then 10 mm long × 12 mm wide × depth 4 by two types of punches. A 6 mm hole was simultaneously punched into two locations. And while measuring the press load required for the punching with a punch, it evaluated by visually observing the state of the punch surface after punching. Moreover, the state of the shearing surface of the hole after punching was evaluated by visual observation.

  In Table 1, the compositions of the lubricating oils 1 to 8 are expressed in parts by weight. “Sulfur content (%)” indicates the ratio (% by weight) of the sulfur content (sulfur atom) contained in the component (a) based on the total amount of the lubricating oil. “Zinc content (%)” indicates the ratio (% by weight) of zinc content (zinc atom) contained in the component (b) based on the total amount of lubricating oil. “Calcium content (%)” indicates the ratio (% by weight) of the calcium content (calcium atoms) contained in the component (c), based on the total amount of the lubricating oil. “Ester content (%)” indicates the ratio (% by weight) of component (d) based on the total amount of lubricating oil.

As can be seen from the results in Table 1, when the lubricant 7 was used, the punch surface after punching was in good condition. Specifically, no seizure, damage, or the like on the surface of the punch was confirmed, and even when a punch having a TiN coating applied to the material of SKD11 was used, no dropout or peeling of the coating was confirmed. . The state of the sheared surface of the hole punched out by the punch was very good, and there were few burrs and sagging around the hole, and a precise hole as planned was formed. On the other hand, when the lubricating oils 1 to 6 and 8 are used, the surface of the punch and the shearing surface of the hole are generally good, but the press load required for punching by the punch increases. It was.
From the above results, it was found that the lubricating oil (lubricating oil 7) used in the metal material pressing method according to the present invention has high performance even in the lubricating oil itself.

Next, a test for evaluating the service life of the mold was performed under the following conditions.
(Evaluation test equipment)
Press machine: AIDA Link press VL-6000 (Production speed: 70 spm)
Material feed: 23.5mm
Work material: SPH440 (plate width: 70 mm, plate thickness: 4.6 mm)
Lubricating oil: “Lubricating oil 7” in Table 1
Lubricating oil supply method: Evenly applied to the surface of the work material with a resin roll Punch 1: SKD11
Punch 2: SKD11 + TiN coating Punch 3: SKD11 + TiAlN coating Punch 4: SKD11 + TiCN coating Dies: SKD11

(Evaluation methods)
After the lubricating oil having the composition of “Lubricating oil 7” in Table 1 is uniformly supplied to the surface of the material to be processed using a resin roll, the punches 1 to 4 are used to make a length of 10 mm × width 12 mm × A hole with a depth of 4.6 mm was simultaneously punched into two places. And while measuring the press load required for the punching by punch, it evaluated how many times punch damage generate | occur | produces. The results are shown in Table 2 below.

  As can be seen from the results in Table 2, it has been found that the service life of the punch in which SKD11 is subjected to TiN coating treatment is the longest.

  Next, a similar test was performed using a surface-treated punch. Specifically, fine particles made of spherical high-speed tool steel (high speed) having an average particle diameter of 60 μm are sprayed on the surface of the punch of SKD11 at a spray speed of 130 m / s to 170 m / s, and then the average particle diameter Fine particles made of a spherical ceramic material of 60 μm were sprayed at a spray speed of 130 m / s to 170 m / s. After the surface treatment, the surface of the punch was further subjected to titanium nitride coating treatment by the PVD method (this is referred to as “punch 5”). The punch 5 was used to measure the press load required for punching, and to evaluate how many times punch damage occurred. The results are shown in Table 3 below.

  As can be seen from the results shown in Table 3, in the case of a die (punch 5) having been subjected to a surface treatment on SKD11 and then subjected to a titanium nitride coating treatment, the die simply having a titanium nitride coating applied to SKD11 ( It was found that the press load required for punching with a punch is smaller than that of the punch 2).

Next, the service life of the mold was evaluated in the following production apparatus. The results are shown in Table 4.
(Production equipment)
Press machine: Fine tool hydraulic press machine (Production speed: 25 spm)
Work material: SPH440 (plate width: 70 mm, plate pressure: 4.6 mm)
Production parts: Reclining parts for automobile seats Lubricating oil used: Lubricating oil 7 (present invention) and Lubricating oil 8 (comparative example)
Lubricating oil supply method: Evenly applied to the surface of the work material with a resin roll Punch used: Punch 5 (present invention) and Punch 2 (comparative example)

As can be seen from the results shown in Table 4, it was found that by combining the punch 5 and the lubricating oil 7, the state of the sheared surface of the press-processed product becomes extremely good. Further, it was found that by combining the punch 5 and the lubricating oil 7, the number of punch damages was about 100,000 times, and the service life of the punch was dramatically increased.
That is, from this result, by pressing a metal material using a lubricating oil (lubricating oil 7) having a specific composition and a die (punch 5) subjected to surface treatment under a specific condition, It has been demonstrated that it is possible to improve the processing accuracy of the press-processed product and to extend the life of the mold compared to the conventional method.

Claims (2)

A method of pressing a metal material using a surface-treated mold in a state where lubricating oil is supplied between the metal material and the mold,
In the surface treatment, fine particles made of high-speed tool steel having an average particle size of 30 μm or more and 80 μm or less are sprayed on the surface of the mold at an injection speed of 130 m / s or more and 170 m / s or less, and then the average particle size is 40 μm or more and 70 μm or less. A process of spraying fine particles made of the ceramic material on the surface of the mold at an injection speed of 130 m / s or more and 170 m / s or less,
The lubricating oil is a lubricating oil obtained by blending a lubricating base oil with a sulfur-based extreme pressure agent, an organic zinc compound, a calcium-based additive, and an ester compound, and in the sulfur-based extreme pressure agent The sulfur content is 5% by weight or more, the zinc content in the organic zinc compound is 0.5% by weight or more, the calcium content in the calcium additive is 0.5% by weight or more, and the ester compound A metal material press working method in which the content of is a lubricating oil of 1.0 wt% or more (“wt%” is based on the total amount of lubricating oil). The metal material pressing method according to claim 1, wherein the metal material is pressed on the surface of the surface-treated metal mold using a metal mold further subjected to titanium nitride coating.