JP2000073182A - Wear-resistant members, their manufacturing methods and applications - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the lubrication of the surface by simple surface treatment at a low cost and to reduce the wear at the time of fitting characteristic of the sliding part of a sliding body, on the surface of a ferrous base material, by transfer forming a coating layer of Al or the like softer than that and having a low friction coefficient in such a manner that the metals are rubbed with each other. SOLUTION: On the surface of a ferrous base material such as carbon steel, austenitic stainless steel, martensitic stainless steel or the like, a coating layer softer than the ferrous base material and having a low friction coefficient such as Al, Sb, Pb, Sn, Ag, Cu, Zn, In, their alloys, graphite or the like is transfer formed by friction. This transfer formation can be executed, e.g. while a base material 1 and a transfer material 2 to form into a coating layer are subjected to pressure adhesion, by rotating either, e.g. the base material 1 and rubbing them and forming a coating layer composed of an alloy layer of the base material 1 and the transfer material 2 on the surface of the base material 1 to a thickness of about 0.5 to 5 μm. In this way, the sliding member good in initial fitness, high in heating resistance, enough in wear resistance and capable of contributing to the prolongation of the service life can be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wear-resistant member having an alloy layer or film which is in contact with each other, moves relative to each other with sliding, and has high compatibility with unlubricated and lubricated mechanical parts, and its manufacture. Laws and uses.

[0002]

2. Description of the Related Art Cast iron, nitrided and carburized surface treatment materials and the like are used in metal and sliding parts such as household and commercial electric appliances and automobile parts in view of abrasion resistance. As a means for improving the wear resistance, it is generally effective to cure the material itself or the surface layer. As a method of curing the material itself, there is a quenching treatment. Methods for hardening the surface layer include the above-described nitriding and carburizing, as well as induction hardening, thermal spraying, welding and the like.
Further, as a film forming technique, there are CVD, PVD, plating and the like. These techniques are actively used from the viewpoint of improving the wear resistance of products. However, it is generally costly. Further, in heat treatment, thermal spraying, welding, and the like, problems such as deformation due to heat occur. In addition, there is a concern that the material produced by any of the methods may cause considerable wear to itself and the mating material at the “fit-in” stage.

[0003] Japanese Patent Application Laid-Open No. 5-98459 discloses that Z
It is disclosed that the corrosion resistance is enhanced by forming a layer of n, Al or an alloy thereof by friction, and Japanese Patent Application Laid-Open No. 63-246505 discloses that a metal lubricating layer is formed on the surface of a ceramic member by friction. .

[0004]

In the process of abrading the sliding part, there is a phenomenon called "conformity" in which the state of the friction coefficient changes from a high state to a low state. This occurs during the process of smoothing or chemically stabilizing the surface.
Generally, the wear of the sliding members shifts from the initial wear to the steady wear before the sliding members “fit together”. Initial wear has been found to be considerably more severe than steady wear. Therefore, if the sliding surface is smoothed with a wear-resistant material before the sliding, it is considered that the abrasion at the time of “fitting” can be reduced.

However, these publications do not disclose forming a coating layer having wear resistance on an iron-based member and further forming an alloy layer on the interface.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wear-resistant member for a sliding body which reduces abrasion at the time of "fit-in" peculiar to a sliding portion, a method of manufacturing the same, and a use thereof.

[0007]

The present invention is characterized in that a coating layer softer than the iron-based substrate and having a low coefficient of friction is transferred and formed on the surface of the iron-based substrate by friction. Wear members. It is preferable that the coating layer has an alloy layer composed of the base material and the coating layer formed at the interface between the base material and the coating layer, and is transferred to the surface of the base material by adhesion.

The coating layer is made of Al, Sb, Pb, Sn, A
g, Cu, Zn, In, their alloys, and at least one of graphite, and a friction coefficient of 0.3.
Hereinafter, 0.15 to 0.31 is particularly preferable.

It is preferable that the substrate is at least one of carbon steel, austenitic stainless steel and martensitic stainless steel.

The coating layer in the present invention preferably has a thickness of 0.5 to 5 μm.

The present invention relates to a method for producing a wear-resistant member, wherein a coating layer softer than the iron-based substrate and having a low coefficient of friction is transferred and formed on the surface of the iron-based substrate by friction. The material and the member to be the coating layer are brought into contact with each other under pressure to rotate at least one of them, and preferably, at the interface between the substrate and the coating layer, an alloy layer of the substrate and the coating layer is formed and the coating layer is formed. Is preferably transferred to the surface of the base material by adhesion.

According to the present invention, there is provided a shaft which rotates in conjunction with a motor, a roller which eccentrically moves by the rotation of the shaft, a cylinder which accommodates the roller, and a cylinder which reciprocates with the movement of the roller. The roller is made of an iron-based member, and the coating layer, which is softer than the iron-based substrate and has a lower friction coefficient, is transferred to the surface of the iron-based substrate by friction. Preferably, the coating layer has an alloy layer composed of the base material and the coating layer at the interface between the base material and the coating layer, and is transferred to the surface of the base material by adhesion. preferable.

First, the concept of the transfer process will be described. FIG. 3 is a diagram in which the transfer material 2 is brought into contact with the base material 1. FIG. 1 shows a cross section of the base material 1 after the transfer test.
FIG. 3 is a diagram in which an alloy layer 3 is formed. FIG. 2 is a cross-sectional view of the substrate 1 after the transfer test, in which a film 4 of the transfer material is formed on the surface of the substrate 1.

That is, the present invention uses the following method as a method for manufacturing a wear-resistant member of the present invention in order to achieve the above object.

In order to reduce the initial wear caused by the "smearing" which is a characteristic phenomenon of the sliding member, at least the surface of the rotating sliding member has higher conformability or wear resistance as one material than the sliding member material. By forming an alloy layer or a film using a material, at least one of the sliding surfaces is smoothed, the coefficient of friction is smaller than in a state where nothing is applied in an actual movable state, and the initial wear due to “fit-in” is reduced. be able to. The sliding member manufactured by this method can reduce wear at the time of actual operation at low cost and can greatly contribute to prolonging the service life and improving the reliability of the product.

Generally, the sliding portion is used in a lubricated state.
Oil lubrication, grease, emulsion, solid lubrication,
And gas lubrication contributes to reducing wear and preventing biting and seizure.

When the metal materials slide with each other, an initial wear occurs due to “fit-in” which is a characteristic phenomenon of the sliding portion. The initial abrasion due to the “fit-in” is caused by the unevenness of the contact surface between the sliding bodies. Therefore, if the sliding surfaces are made as smooth as possible from the beginning with a material having high conformability or wear resistance, the initial wear is reduced.

According to the present invention, one of the two sliding surfaces is initially "familiar" with a low melting point and soft metal on one of the sliding surfaces.
, Sb, Pb, S with a low melting point and a soft metal to reduce the friction coefficient in order to improve the wear resistance
A plate material of n, Ag, Cu, Zn, In, Sn, and graphite is brought into pressure contact to form an alloy layer or film using surface flash heat and surface plastic flow. In this process, an appropriate load and speed must be selected so that the two sliding surfaces do not bite or seize. If the machined surface becomes rougher than the initial machined surface, the coefficient of friction at the time of “fitting-in” increases, which causes an increase in wear.

The sliding member manufactured by the above-described method is inexpensive and has an alloy layer or a film of the transfer material formed on the surface of at least one of the slide members in the actual operation. As a result, the "fit-in" property is improved and wear is reduced.

[0020]

(Embodiment 1) Table 1 shows the transfer materials subjected to the test. FIG. 4 shows the outline of the test section of the bench type bearing tester used for the transfer test. Substrate 1 in test chamber 5
Is set, and the transfer material 2 is attached to a fixed test piece jig attached to the torque arm 7.
A test is performed by applying a predetermined load on the substrate 1 and rotating the substrate 1 at a predetermined rotation speed. Here, the base material 1 is carbon steel S4 for machine structure.
5C was used. Transfer material 2 is Al, Sb, Pb, Sn, A
g, Cu, Zn, In, graphite, Cu + Pb, Sn + P
b, Sn + Sb, Sn + Pb + Zn, Sn + Cu + S
b, Zn + Al + Cu. Test is load 5kg-30k
g, rotation speed 200 rpm (0.31 m / s)-1000 rpm
(1.57 m / s) in air. Upon visual inspection after the test, each transfer material was uniformly covered on the S45C surface of the substrate 1 by adhesion. EPMA
As a result, the composition of each test transfer material shown in Table 1 was detected. When the transferred cross section was polished and subjected to surface analysis by EPMA, components of each transferred material were detected at a portion several μm from the end face. Table 2 shows values obtained by measuring the thickness of the film from the analysis results. In addition, in addition to In, C and Fe components were also detected at the end face of the S45C cross section of Example No. 8. Therefore, it can be seen that this transfer boundary is an alloy layer alloyed by frictional heat during sliding. Others had an alloy layer formed at the interface.

The S45C surface of the substrate 1 was blasted with an iron lump to a surface roughness of 1 to 4 μm and subjected to the same transfer test as described above. As a result, transferability was further improved.

[0022]

[Table 1]

Next, the coefficient of friction and the seizure time of the test piece manufactured according to the present invention were determined. Figure 4 shows the friction coefficient measurement test.
The tabletop type bearing tester shown in FIG. S45C after the transfer test was used for the base material 1 serving as a movable piece, and S45C was also used for the fixed piece. For comparison, a test using S45C before the transfer test was performed on the movable piece. The test was performed with a load of 2 kg,
The rotation was performed at a rotation speed of 500 rpm (0.79 m / s) in the atmosphere until burning occurred. Table 2 shows the results of friction coefficient measurement and baking time. Here, the place where the frictional force suddenly increases was defined as the seizure time. The coefficient of friction of each transfer material is smaller than that of the as-machined S45C surface. Further, the seizure time of each transfer treatment material at which the friction coefficient sharply increased was longer than that of the test piece as-machined in S45C.

The S45C surface of the substrate 1 was blasted with an iron lump to a surface roughness of 1 to 4 μm and subjected to the same transfer test as described above. As a result, transferability was further improved.

[0025]

[Table 2]

(Example 2) Table 3 shows the transfer materials used for the test. Base material 1 is SUS304 of austenitic stainless steel
Was used. The test conditions are the same as in Example 1. Visually after the test, each transfer material was uniformly covered on the SUS304 surface of the base material 1 by adhesion. EPM
As a result of the surface analysis in A, the components of each test transfer material shown in Table 3 were detected. When the transferred cross section was polished and subjected to surface analysis by EPMA, components of each transferred material were detected at a portion several μm from the end face. Table 4 shows values obtained by measuring the thickness of the film from the analysis results. In addition, in addition to In, C, Fe, Cr, Ni
Was also detected. Therefore, it can be seen that this surface is an alloy layer. Others had an alloy layer formed at the interface.

[0027]

[Table 3]

Next, the friction coefficient and the seizure time of the test piece manufactured according to the present invention were determined. Figure 4 shows the friction coefficient measurement test.
The tabletop type bearing tester shown in FIG. SUS304 after the transfer test was used for the base material 1 to be a movable piece, and
SUS304 was used. For comparison, before moving test
A test using SUS304 was also performed. The test conditions are the same as in Example 1. Table 4 shows the results of friction coefficient measurement and baking time. The coefficient of friction of each transfer material is smaller than that of the as-machined SUS304 surface. In addition, the seizure time of each transfer treatment material at which the friction coefficient sharply increased was longer than that of the test piece as machined with SUS304.

When the surface of the SUS304 of the substrate 1 was blasted with an iron lump to a surface roughness of 1 to 4 μm and subjected to the same transfer test as described above, the transferability was further improved.

[0030]

[Table 4]

(Example 3) Table 5 shows the transfer materials used in the test. Base material 1 is SUS403 of martensitic stainless steel
Was used. The test is the same as in Examples 1 and 2. Upon visual inspection after the test, each transfer material was uniformly covered on the SUS403 surface of the base material 1 by adhesion. These aspects are EP
As a result of surface analysis by MA, the components of each test transfer material shown in Table 5 were detected. When the transferred cross section was polished and subjected to surface analysis by EPMA, components of each transferred material were detected at a portion several μm from the end face. Table 6 shows values obtained by measuring the thickness of the film from the analysis results. In addition, in addition to In, components of C, Fe, and Cr were detected at the end face of the S45C cross section of Example No. 8. Therefore, it can be seen that this surface is an alloy layer. Others had an alloy layer formed at the interface.

[0032]

[Table 5]

Next, the coefficient of friction and the seizure time of the test piece manufactured according to the present invention were determined. Figure 4 shows the friction coefficient measurement test.
The tabletop type bearing tester shown in FIG. SUS403 after the transfer test is used for the base material 1 that becomes the movable piece, and
SUS403 was used. For comparison, before moving test
A test using SUS403 was also performed. The test conditions are the same as in Examples 1 and 2. Table 6 shows the results of friction coefficient measurement and baking time. The coefficient of friction of each transfer material is smaller than that of the as-machined S45C surface. In addition, the seizure time of each transfer treatment material at which the friction coefficient sharply increased was longer than that of the test piece as machined with SUS403.

When the surface of the SUS403 of the substrate 1 was blasted with an iron lump to a surface roughness of 1 to 4 μm and subjected to the same transfer test as described above, the transferability was further improved.

[0035]

[Table 6]

Embodiment 4 FIG. 5 shows the entire structure of a rotary compressor for a refrigerator. FIG. 6 shows a cross section of the compression section of the refrigerator compressor of FIG. The main components are an upper bearing 13, a lower bearing 14 for supporting the shaft 9 in the chamber 8, a journal bearing for the roller 12, a vane 11 and a cylinder 10.
And a thrust bearing of the vane 11 and the roller 12. In these bearings, the surface pressure increases, the lubricating oil film decreases, and the viscosity of the refrigerating machine oil decreases due to the dilution of the refrigerant due to the miniaturization and high performance of the product. In particular, wear conditions between the vane-to-roller, the roller-to-shaft, and the bearing-to-shaft become severe, and excellent wear resistance and seizure resistance are required.

According to the methods of Examples 1 to 3, FC25 was added to the substrate.
0 was applied to the entire surface of the roller of the refrigerator compressor, and a roller-to-vane actual machine test was performed. For comparison, a conventional compressor using untreated FC250 as a roller material was also tested. The test atmosphere was HAF134a refrigerant and ester oil. The operation time was 2,000 hours. As a result, the F of the conventional compressor
Although abrasive wear marks were observed on C250, no wear marks or the like were generated on the surface of the material of the present invention, and the appearance was almost the same as before the test, confirming the effect of the material of the present invention.

Although the present invention has been described with respect to a compressor for a refrigerator, further excellent functions can be exhibited by applying the present invention to other mechanical devices having a sliding portion.

[0039]

According to the present invention, an alloy layer or film having good lubrication can be easily formed on one metal surface at low cost by rubbing the metal, and a machine having a sliding portion by these. In the apparatus, the initial “fit-in” is good, the seizure resistance is high, the abrasion resistance is high, and the life of the machine can be extended.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a substrate after a transfer test.

FIG. 2 is a cross-sectional view of a substrate after a transfer test.

FIG. 3 is a conceptual diagram of a transfer process.

FIG. 4 is a configuration diagram of a tabletop wear tester used for a transfer test and a friction coefficient measurement.

FIG. 5 is a partial sectional perspective view showing the entire structure of a rotary compressor for a refrigerator.

FIG. 6 is a sectional view of a compression unit of the rotary compressor for a refrigerator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base material, 2 ... Transfer material, 3 ... Alloy layer, 4 ... Transfer material film, 5
... test chamber, 6 ... load spring, 7 ... torque arm, 8 ... chamber, 9 ... crankshaft, 10 ... cylinder, 11 ... vane, 12 ... roller, 13 ... upper bearing, 14 ... lower bearing.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mami Taguchi 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in Hitachi Research Laboratory, Hitachi, Ltd. 3H029 AA01 AA04 AA15 AB01 AB03 BB44 BB50 CC05 CC38 4K044 AA02 AA03 BA06 BA08 BA10 BA18 BC01 CA51

Claims (5)

[Claims] 1. A wear-resistant member, wherein a coating layer softer than the iron-based substrate and having a low coefficient of friction is transferred and formed on the surface of the iron-based substrate by friction. 2. The method according to claim 1, wherein said coating layer is made of Al, S
A wear-resistant member comprising at least one of b, Pb, Sn, Ag, Cu, Zn, In, an alloy thereof, and graphite. 3. A wear-resistant member according to claim 1, wherein said base material is at least one of carbon steel, austenitic stainless steel, and martensitic stainless steel. 4. An iron-based substrate having a surface softer than the iron-based substrate,
And a method for producing a wear-resistant member that forms a coating layer having a low friction coefficient by friction, wherein at least one of the iron-based substrate and the member to be the coating layer is brought into pressure contact with each other and rotated, and A method for producing a wear-resistant member, comprising transferring the coating layer to a surface. 5. A shaft that rotates in conjunction with a motor, a roller that eccentrically moves by rotation of the shaft, a cylinder that houses the roller, and a cylinder that reciprocates with the movement of the roller. And a roller formed of an iron-based member, and a coating layer that is softer than the iron-based substrate and has a lower coefficient of friction is transferred to the surface of the iron-based substrate by friction. A rotary compressor characterized by being performed.