JPH09314253A - Member for plastic working of metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the service life by applying a member for plastic working of soft metal to various members in contact with soft metal in the plastic working such as bending, rolling, pulling-out, shearing, drawing, compression and form rolling of a member for plastic working of soft metal. SOLUTION: In a member for plastic working of soft metal such as aluminum and copper, or soft metal on the surface of which an organic resin film is formed, the surface of a member in contact with the soft metal or the organic resin film is formed of a hard carbon film of 0.05-2 in the peak intensity ratio to be expressed by H1 /H2 where peaks are present in 1340±40cm<-1> and 1160±40cm<-1> in the Raman spectroscopic analysis, H1 is the highest peak intensity of the peaks present in 1160±40cm<-1> , and H2 is the highest peak intensity present in 1340±40cm<-1> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft metal, an alloy containing such a soft metal as a main component, soft iron, or a metal member having a metal surface coated with an organic resin film. The present invention relates to a metal plastic working member used for plastic working such as bending, drawing, compression and rolling.

[0002]

2. Description of the Related Art Aluminum, copper, zinc, tin and lead,
Metal plastic working members used when plastic working soft iron etc. are in contact with the above-mentioned metal to be worked and in some cases plastically deform while sliding, so the material of the member has high wear resistance and friction. It is required that the coefficient is low, that is, the sliding property is excellent.

Therefore, conventionally, as a member for processing a soft metal, one made of cemented carbide is most commonly used, and it is also proposed to use cermet or ceramics such as alumina and zirconia. There is.

Further, as one means for improving wear resistance, it has been conventionally known to form a diamond film having high hardness on the surface of a member which comes into contact with a metal.

[0005]

However, in the plastic working of soft metal, as the working speed becomes faster due to its mass productivity and the working conditions become severe, the wear of the working member becomes more severe, and the conventional super-compact The wear of members made of hard alloys, cermets and ceramics also tends to be extremely advanced. In particular, aluminum, copper,
When processing a soft metal such as soft iron or a metal with an organic resin film formed, the voids existing on the surface of the sintered body are clogged with the soft metal or organic resin film, causing welding or adhesion and causing a build-up phenomenon. However, there is a problem that the surface of the metal to be processed becomes rough after processing.

As one method for improving the wear resistance of the working member, it is conceivable to coat the surface of the working member with a diamond film of high hardness. However, a conventional diamond film is generally formed by a vapor phase growth method such as a microwave CVD method, and unevenness due to diamond crystal grains exists on the surface thereof, and voids also exist in the film. Since unevenness and voids exist on such a surface, even if the wear resistance is improved to some extent, the build-up phenomenon cannot be prevented.

Further, recently, there is also a metal member in which a protective film or a film made of an organic resin for preventing elution of metal components is formed on the surface of a soft metal. When such a metal member is plastically processed, There was a problem that the organic resin adhered to the surface of the processing member.

[0008]

As a result of repeated studies on the method for solving the above-mentioned problems, the present inventors have found that a metal to be processed made of a soft metal or a member having an organic resin film formed on the surface thereof. On the surface of the member that is in contact with the organic resin film in 1600 ± 40c in Raman spectrum
It was found that by forming a hard carbon film having peaks at m ⁻¹ and 1340 ± 40 cm ^−1, it is possible to provide a plastic working member having extremely excellent wear resistance and excellent productivity without build-up phenomenon. I arrived.

That is, the metal plastic working member of the present invention is a working member for plastic working a soft metal or a soft metal having an organic resin film formed on the surface thereof. The surface of the member in contact with is 1340 ± 40 cm ^-1 and 1160 ± in the Raman spectrum.
There is a peak at 40 cm ^-1 and 1160 ± 40 cm
^Where H ₁ is the strongest peak intensity among ⁻¹ peaks and H ₂ is the highest peak intensity among 1340 ± 40 cm ⁻¹ peaks, it is expressed as H ₁ / H _2. It is characterized by comprising a hard carbon film having a peak intensity ratio of 0.05 to 2.

Further, the hard carbon film is formed on the surface of a base material made of a metal or a sintered body, and an intermediate layer containing at least diamond and metal carbide is provided between the hard carbon film and the base material. Is present.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The metal plastic working member according to the present invention is for working a soft metal, and the soft metal is specifically selected from the group consisting of aluminum, copper, zinc, tin and lead. At least one kind of metal, an alloy containing them as a main component, soft iron and the like can be mentioned. The processing member of the present invention is also applicable to the above-mentioned soft metal having an organic resin film formed on the surface thereof. Examples of the organic resin film formed on the surface include polyethylene terephthalate (PET), polyethylene, polypropylene, polyvinyl alcohol, nylon and the like.

The metal plastic working member according to the present invention has a Raman spectroscopic analysis spectrum chart in which 1 is shown at a position where the metal and the organic resin film formed on the metal surface are in contact with each other.
A hard carbon film having peaks at 160 ± 40 cm ⁻¹ and 1340 ± 40 cm ⁻¹ is formed. This hard carbon film is mainly composed of diamond, but a generally known diamond film is composed of high-purity diamond and has a structure in which carbon atoms are bonded by SP ³ hybrid, and has a Raman spectrum of 1340. ± 40c
It has a peak only at m ^-1 , and if it contains carbon having a graphite structure that is bonded by SP ² hybridization, it has a broad peak near 1500 to 1600 cm ^-1 .

On the other hand, the hard carbon film according to the present invention is 1160 ± 40 cm in addition to 1340 ± 40 cm ^−1.
It has a peak at ^-1 . This 1160 ± 40c
The peak at m ^-1 is considered to mean that although it has a diamond structure, the period of the crystal is short because it is composed of fine crystal diamond particles. Therefore,
In the hard carbon film of the present invention, the diamond crystal is composed of extremely fine particles, and is excellent in flatness without the unevenness caused by the conventional diamond crystal. Further, even if it contains a trace amount of graphite structure, it has high hardness and wear resistance.

Therefore, when the hard carbon film is formed on the surface of a predetermined base material, even if it is formed on the surface of the base material of any shape, a smooth and dense film surface conforming to the surface shape of the base material can be formed. Even when a soft metal is used for bending, or when the surface that contacts the metal is required to have high smoothness, such as a wire drawing die, finishing the base metal surface to the desired surface roughness results in excellent smoothness. It is possible to form a hard carbon film. Even if it is necessary to polish the film surface, it can be more easily polished than a conventional diamond film and a film surface without voids can be formed.

Further, since the hard carbon film of the present invention is a dense film and has no defects such as irregularities and voids unlike the conventional diamond film, it has a build-up phenomenon of soft metal and an organic resin processing member. Adhesion can be prevented.

The peak intensity at 1160 ± 40 cm ⁻¹ in the Raman spectrum of the hard carbon film of the present invention will be specifically described. In the Raman spectrum curve obtained as shown in FIG. 1, 1100 cm ⁻¹ and 17
Pull the hatched between positions 00cm ^-1, this as a baseline, H ₁ the highest intensity peak intensities of the peaks present in 1160 ± 40cm ^-1, 1340 ± 40cm
High peak intensity of most intense among the peaks present to ^-1 and H _2. At this time, it is important that the peak intensity ratio represented by H ₁ / H ₂ is 0.05 to 2.

If the peak intensity ratio is too small, the diamond crystal particles grow too much, voids are generated in the film, the surface roughness of the film is increased, the wear resistance is lowered, and the build-up of soft metal is increased. The phenomenon and the adhesion of the organic resin film are likely to occur. On the other hand, if the peak intensity ratio is too large, the presence of amorphous diamond increases, and the hardness of the hard carbon film itself may decrease, and the wear resistance may decrease. This peak intensity ratio is desirably 0.1 to 1.0.

According to the metal plastic working member of the present invention, it is desirable that the hard carbon film is coated on the surface of a predetermined base material. In that case, the hard carbon film is required to have high adhesion to the base material. Examples of the base material type of the metal-working member include ceramics such as silicon nitride, silicon carbide, alumina and zirconia, and metals such as titanium alloys, cemented carbides, cermets and stainless steels. Among these, silicon nitride, silicon carbide, cemented carbide, cermet and titanium alloy are preferable. These base materials may be used as they are, or may be formed by forming these base material types as thin films on the surface of another member by a thin film forming technique such as a vapor phase growth method.

In order to improve the adhesion of the hard carbon film to the base material, an intermediate layer made of a composite of at least diamond and metal carbide is interposed between the base material surface and the hard carbon film. It is possible to form a hard carbon film having extremely good adhesion.

The reason why the adhesion strength between the hard carbon film and the base material is improved by interposing such an intermediate layer is considered as follows. Atoms are bonded by intervening electrons, but in general, electrons are shared by both atoms rather than ionic bonds, in which electrons between atoms are present on one side and bonded by electrical connection. An existing covalent bond has a stronger binding force. Diamond has a strong bonding force because it is constituted by a covalent bond of carbon. Therefore, in order to improve the adhesion strength between diamond and a different compound, it is considered that a covalent compound having a similar bonding mode is desirable. Also, it seems that a compound containing carbon which is a component of diamond has better consistency. There are many metal carbides, most of which are mainly ionic bonds. As the covalent bond carbide, there are silicon carbide and boron carbide, but silicon carbide is most preferable in the processing member of the present invention.

By forming such an intermediate layer containing a mixture of metal carbide and diamond between the hard carbon film and the base material, the adhesion strength between the hard carbon film and the base material is improved. In addition, the diamond and the metal carbide do not exist in a layer-separated state, but have a structure in which the metal carbide surrounds the diamond. This improves the adhesion.

As a method for producing a hard carbon film in the present invention, a so-called plasma CVD method has been used, in which a carbon film is conventionally used to generate plasma by microwaves or high frequencies to form a carbon film on a predetermined substrate surface. Alternatively, the hot filament method is the mainstream. However, in the plasma CVD method, since the plasma generation area is small,
The area in which a film can be formed is small, and the area in which a film can be formed is generally about 20 mm in diameter, and its application as a processing member is limited. In addition, when the pressure is too high or the plasma density is too low, if the substrate has a complicated structure or has a curved surface structure, uniform plasma along the structure cannot be obtained, and the film thickness distribution becomes uneven. Prone.

On the other hand, in the hot filament CVD method, the filament is easily broken, and it is necessary to install the filament in conformity with the shape of the base material in order to suppress the variation in the film thickness, and the apparatus lacks versatility. have.

On the other hand, according to the so-called electron cyclotron resonance plasma CVD method in which a magnetic field is applied to the plasma generation region in the plasma CVD method, a low pressure (1 t
or less), high-density plasma can be obtained, so that plasma can be uniformly generated in a wide area, and a film can be uniformly formed in an area about 10 times as large as that of a normal plasma CVD method. It can be performed.

Therefore, the electron cyclotron resonance plasma CVD method (ECR plasma CVD method) will be described here as an example. In this method, a reaction gas is introduced into a reaction furnace in which a predetermined base material is installed, and at the same time, 2.4 is introduced.
A microwave of 5 GHz is introduced. At the same time, a magnetic field of a level of 875 Gauss or more is applied to this region. This allows the electrons to have a cyclotron frequency f = eB /
2πm (m: mass of electron, e: charge of electron, B:
Cyclotron motion is generated based on the magnetic flux density). When this frequency coincides with the microwave frequency (2.45 GHz), it resonates and electrons are remarkably absorbed by the energy of the microwave, accelerated, collide with neutral molecules and cause ionization to generate high-density plasma. Become like At this time, the temperature of the base material was 150 to 1000 ° C., and the furnace pressure was 1 × 10 ^−2.
１1 torr.

According to this method, the base material temperature during film formation,
By changing the furnace pressure and the reaction gas concentration, the components and the like of the formed hard carbon film change. In particular,
As the pressure in the furnace increases, the area of the plasma decreases, and the growth rate of the film decreases, but the crystallinity tends to improve. Also, when the concentration of the reaction gas increases, the size of the particles constituting the film tends to decrease, and the crystallinity tends to deteriorate. Specifically these conditions by controlled appropriately as described in the examples below, it is possible to control the H ₁ / H ₂ ratio described above.

In the above film forming method, when the metal plastic working member of the present invention is produced, the hard carbon film uses hydrogen and carbon-containing gas as raw material gases. Examples of the carbon-containing gas used include, for example, alkanes such as methane, ethane, and propane; alkenes such as ethylene and propylene; alkynes such as acetylene; aromatic hydrocarbons such as benzene; cycloparaffins such as cyclopropane; And cycloolefins such as cyclopentene. Oxygen-containing carbon compounds such as carbon monoxide, carbon dioxide, methyl alcohol, ethyl alcohol and acetone, and nitrogen-containing carbon compounds such as mono (di, tri) methylamine and mono (di, tri) ethylamine are also used as carbon source gases. Can be used. These can be used alone or in combination of two or more.

In order to form the intermediate layer made of a mixture of diamond and silicon carbide as described above, after performing a diamond nucleation treatment, if desired, hydrogen, a carbon-containing gas and a silicon-containing gas are used as reaction gases. To introduce. As the silicon-containing gas, silicon tetrafluoride,
In addition to halides such as silicon tetrachloride and silicon tetrabromide, oxides such as silicon dioxide, silane compounds such as mono (di, tri, tetra, penta) silane and mono (di, tri, tetra) methylsilane, and trimethyl And silanol compounds such as silanol. These can be used alone or in combination of two or more.

As described above, according to the present invention, since the hard carbon film of the plastic working member which is in contact with the soft metal is mainly composed of diamond having a fine grain structure, it is dense and has voids or the like on the film surface. There are no defects. Therefore, if this hard carbon film is formed on the sliding surface of the soft metal during plastic working, the build-up phenomenon of the soft metal can be prevented and the life of the member can be extended. Further, even when an organic resin film is formed on the surface of the metal to be processed, it is effective for preventing the adhesion of the organic resin to the processing member.

Further, by interposing an intermediate layer containing at least diamond and metal carbide between the surface of the member and the hard carbon film, the adhesion of the hard carbon film to the base material can be enhanced, It is possible to prevent the hard carbon film from peeling off from the base material.

[0031]

【Example】

(Example 1) in an oven at electron cyclotron resonance plasma CVD apparatus, silicon nitride sintered bodies as the base material (Y ₂ O ₃ 3% by weight, Al ₂ O ₃ 4% by weight containing), titanium alloy (Ti-6A
1-4V) was installed.

There, H ₂ 297 sccm, CH ₄ 3s
ccm gas, gas concentration 1%, base material temperature 650
° C., 3 hours to at reactor pressure 0.1 torr, after generating the diamond nuclei, H ₂ gas as the source gas, C
Using H ₄ gas and Si (CH ₃ ) ₄ gas, the gas concentration is 1% at a rate of H ₂ 297 sccm CH _{4 3} sccm Si (CH ₃ ) ₄ 0.3 sccm, the base material temperature is 650 ° C., and the furnace pressure is 0.05 torr. Electron cyclotron resonance (E
CR) A magnetic field having a maximum intensity of 2 kGauss was applied by a plasma CVD method, and a microwave power of 3.0 KW was applied.
Film formation was performed for 0 hour to form an intermediate layer having a thickness of 1.0 μm in which diamond and silicon carbide were mixed.

Further, in Table 1, for sample No. 4, silicon carbide was prepared in exactly the same manner as above except that the intermediate layer was formed at a gas ratio of H ₂ gas of 300 sccm Si (CH ₃ ) ₄ gas of 0.3 sccm. An intermediate layer made of was formed to a thickness of 1 μm and evaluated in the same manner.

Next, H ₂ gas, CH ₄ gas, and CO ₂ gas having a purity of 99.9% or more were used on the intermediate layer, and the gas ratio, gas concentration, base material temperature, and furnace temperature shown in Table 1 were used. Film formation was performed under pressure to form a hard carbon film of 4 μm.

[0035] For the formed hard carbon film, subjected to Raman spectrum analysis of the film surface, draw a line between positions 1100 cm ^-1 and 1700 cm ^-1 from the Raman spectrum chart, which was the baseline, 1160 ± 40
The peak intensity of the maximum peak existing at cm ^-1 is H ₁ , 13
The peak intensity of the maximum peak present in 40 ± 40 cm ^-1 as H _2, was calculated intensity ratio expressed by H ₁ / H _2.
In Table 1, charts of Sample No. 3 and Sample No. 9 are shown in FIGS. The laser used as an oscillation source in the Raman spectroscopic analysis was an Ar laser (oscillation line 48).
8.0 nm).

Then, the sliding characteristics of the obtained substrate were evaluated by the pin-on-disk method. The sliding test conditions were room temperature, air, and no lubrication under a load of 39.2N,
The sliding speed was 2 m / sec and the time was 24 hours. The pin used was made of aluminum with a radius of curvature R of 4.763 mm. Table 1 shows the sliding time and the reason for stopping the sliding test.

Example 2 On the surface of the press-molding die base material made of the silicon nitride sintered material or Ti alloy used in Example 1, an intermediate layer of 1.0 μm and an intermediate layer were formed in the same manner as in Example 1. A hard carbon film of 3.0 μm was formed.

Using this pressing die, P
An experiment was conducted by bending a 300 μm-thick aluminum thin plate in which ET (polyethylene terephthalate) resin was formed with a thickness of 10 μm by pressing, and the maximum was 1
I went, 000,000 times. The test was stopped when the adhesion of the PET resin to the mold surface was detected. The results are shown in Table 1.

(Comparative Example 1) Using a cemented carbide, Example 1
Then, the same sliding test and press working test as in Example 2 were performed, and the results are shown in Table 1, Sample No. 15.

Comparative Example 2 Using the silicon nitride sintered material used in the example as a base material, the intermediate layer was formed by the microwave CVD method at the same gas ratio as that of the example and the gas concentration of 1%. After forming the film for 10 hours under the conditions of the material temperature of 950 ° C. and the furnace pressure of 30 torr, the film was further formed under the conditions shown in Sample No. 9 of Table 1 to form a hard carbon film of 4 μm.

A sliding test and a press working test similar to those in Examples 1 and 2 were conducted for this, and the results are shown in Table 1, Sample No. 9.

[0042]

[Table 1]

According to the results shown in Table 1, H ₁ / H ₂ is 0.0
The samples of the present invention each having a hard carbon film of Nos. 5 and 2 formed showed no wear or aluminum adhesion even after 24 hours in a pin-on-desk test with aluminum, and also had a million times in a press working test. No organic resin adhesion was observed even after pressing, and the processed product was in a good state. Further, in terms of the adhesion of the hard carbon film, there was a part of peeling after the test in the intermediate layer in which the intermediate layer was made of only metal carbide.

As a comparative example, in the conventional cemented carbide,
In the sliding test, metal adhesion was observed after 30 minutes, and in the press working test, organic resin adhesion was observed after 500 times. In addition, a hard carbon film manufactured by a microwave CVD method or the like,
Samples Nos. 1, 9 and 10 in which the ratio of H ₁ / H ₂ was less than 0.05 depending on the film forming conditions were all inferior in 24-hour durability due to metal deposition. Also, in the press working test, adhesion of the organic resin was recognized after 800,000 times. Also, the sample No. _{1 having a} H ₁ / H ₂ ratio of more than 2.
In Nos. 7, 8 and 14, the hardness of the hard carbon film was lowered and the abrasion after the test was remarkable.

When the sliding test and the press working test of Example 1 were conducted on copper, zinc, tin, lead and soft iron, similar test results were obtained.

[0046]

As described above in detail, the metal plastic working member of the present invention is a part which is free from the adhesion and the adhesion of the soft metal or the organic resin film on the contact surface with the soft metal and has excellent durability. Can be provided. As a result, by applying it to various parts that come into contact with soft metal during plastic working such as bending, rolling, drawing, shearing, drawing, compression, rolling, etc. The life can be extended.

[Brief description of drawings]

FIG. 1 shows a hard carbon film (Sample No. in Table 1) of the present invention.
It is a Raman spectroscopy spectrum figure of 3).

FIG. 2 is a Raman spectrum diagram of a conventional hard carbon film (sample No. 9 in Table 1).

Claims (3)

[Claims] 1. A processing member for plastically processing a soft metal or a soft metal having an organic resin film formed on the surface thereof, wherein the member surface in contact with the metal or the organic resin film has a Raman spectroscopic spectrum. 1340 ± 40 cm
^-1 and 1160 ± 40 cm ^-1 with peaks, and 11
When the strongest peak intensity among the peaks existing at 60 ± 40 cm ⁻¹ is H ₁ and the strongest peak intensity among the peaks existing at 1340 ± 40 cm ⁻¹ is H ₂ , H ₁ / H ₂ A metal plastic working member comprising a hard carbon film having a peak intensity ratio of 0.05 to 2 represented by 2. A member for metal plastic working, wherein the hard carbon film is formed on a surface of a base material made of a metal or a sintered body. 3. The metal plastic working member according to claim 3, wherein an intermediate layer containing at least diamond and metal carbide is present between the hard carbon film and the base material.