JPH0987830A - Sliding member for compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sliding member for compressor, excellent in impact resistance as well as in wear resistance, minimal in chipping, peeling, etc., of surface, and further minimal in wear of mating member. SOLUTION: A mixed ion plating film, consisting of CrN and Cr2 N or CrN, Cr2 N and metallic Cr, is formed on the surface of a sliding member for compressor. This film has a composition consisting of 45.0-98.0wt.% CrN and the balance Cr2 N in the case of binary system or consisting of 45.0-98.0wt.% CrN, 0.5-15.5wt.% Cr, and the balance Cr2 N in the case of ternary system. It is preferable that the film is formed after the surface of the base material is nitrided or the porosity of the film is regulated to 0.5-20.0%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding member for a compressor, and more particularly to a sliding component such as a vane or a roller that relatively slides in the compressor.

[0002]

2. Description of the Related Art Various compressors are used for heat exchange in air conditioners, refrigerators and the like. The compressor includes, for example, a rotary hermetic compressor,
There are reciprocating hermetic compressors, semi-hermetic compressors for car air conditioners, etc., and some sliding parts are incorporated inside any compressor. For example, in a rotary compressor, a roller is eccentrically supported in its roller housing, while a vane is held in a vane groove formed in the roller housing via an elastic body such as a spring. The tip (nose) of the vane protruding from the vane groove is in sliding contact with the outer peripheral surface of the roller. In such a rotary compressor, the nose portion of the vane and the outer peripheral surface of the roller relatively slide as the roller rotates. Further, since the vane reciprocates in the vane groove along the radial direction of the roller housing in accordance with the eccentric rotation of the roller, the side surface portion of the vane and the inner wall of the vane groove also relatively slide. further,
The roller is supported by the shaft with or without a crank, and the shaft receives pressure from the spring in the vane groove and the inner wall of the cylinder via the roller, and is pressed against the bearing that supports the shaft by this pressure. , Rotates at high speed with a slightly curved shape. Therefore, the outer surface of the shaft and the inner surface of the bearing also relatively slide.

As described above, the sliding member that relatively slides in the compressor is required to have excellent wear resistance. For example, Japanese Unexamined Patent Publication No. 64-63692 discloses a sliding member for a compressor such as a vane in which a coating layer is formed on a base material for the purpose of improving wear resistance during sliding. ing. This coating layer has a relatively low processing temperature (150 to 4).
It is possible to form a dense and smooth coating layer while preventing deterioration of a base material made of, for example, an aluminum alloy or an iron-based alloy, and is therefore formed mainly by an ion plating method. There is.

However, in the case of the ion plating method, there was a problem that the impact resistance was poor because the hardness difference between the base material and the coating film was large and the coating film was easily peeled off. Specifically, the hardness of high speed tool steel (SKH51) widely used as a base material is about Hv750, whereas the hardness of the titanium nitride coating film by the ion plating method is about Hv2500. There is a considerable hardness difference between the two.

On the other hand, in a vane (Japanese Patent Laid-Open No. 60-228794) in which a base material such as a sintered alloy is subjected to a nitriding treatment, for example, a high speed tool steel (SK) is one of the base materials.
The hardness of H51) is about Hv750 as described above, whereas when it is subjected to a nitriding treatment, the hardness is Hv125.
It is about 0. Therefore, although the hardness of the base material is increased and the wear resistance is considerably improved, there is a problem that the wear resistance under severe environmental conditions is not always sufficient.

Further, in both cases of the ion plating method and the nitriding treatment, the compatibility of the vanes with the rollers and the vane grooves in terms of wear is not necessarily ideal, so it is desired to reduce the opponent attack property as much as possible. There is.

[0007]

The present invention has been accomplished in view of the above circumstances, and an object thereof is not only excellent in wear resistance but also prevention of peeling and cracking of a coating film. Another object of the present invention is to provide a sliding member for a compressor having both sufficient impact resistance and excellent wear compatibility capable of reducing the amount of wear of a mating member.

[0008]

In the present invention, in order to achieve the above object, Cr is formed on the surface of a sliding member for a compressor.
Mixtures or CrN type chromium nitride and Cr ₂ N-type chromium nitride and metallic Cr and N-type chromium nitride and Cr ₂ N-type chromium nitride
And an ion plating film made of a mixture having a specific composition. Then, preferably, these films are formed after the base material is subjected to a nitriding treatment in advance, and
The porosity of the ion plating film was specified.

That is, first of all, the present invention relates to a sliding member for a compressor, which relatively slides in the compressor.
CrN-type chromium nitride and C in at least one sliding surface area
An ion plating film made of a mixture with r ₂ N-type chromium nitride is formed, and the mixing composition ratio of the ion plating film is CrN-type chromium nitride: 45.0 to
The present invention provides a sliding member for a compressor, characterized in that 98.0% by weight and Cr ₂ N-type chromium nitride: balance.

Secondly, a sliding member for a compressor which relatively slides in the compressor, wherein CrN-type chromium nitride and Cr ₂ N-type chromium nitride are provided in at least one sliding surface area thereof. An ion plating film made of a mixture with metallic Cr is formed, and the mixing composition ratio of the ion plating film is CrN-type chromium nitride: 45.0 to 98.
0 wt%, Cr: 0.5-15.5 wt%, and Cr ₂
Provided is a sliding member for a compressor, characterized by N-type chromium nitride: the rest.

In a preferred embodiment, a nitride layer is formed on the base material in at least one sliding surface region of the compressor sliding member, and the ion plating film is formed on the nitride layer. The first characterized in that
And a second sliding member for a compressor.

As still another preferred aspect, the first and second compressor sliding members are characterized in that the ion plating film has a porosity of 0.5 to 20.0%. To do. Note that the above two preferable modes may be added not only to the first and second compressor sliding members, but also to a combination of both.

The sliding member of the present invention has CrN on its sliding surface.
Binary ion plating coating consisting of a mixture of a specific composition of the type chromium nitride and Cr ₂ N-type chromium nitride, or CrN type chromium nitride and Cr ₂ N-type chromium nitride and the metal Cr
And a ternary ion-plating film made of a mixture having a specific composition In these films, CrN crystals (cubic) and Cr ₂ N, which have different properties and crystal systems, are used.
And hexagonal crystals are intricately intertwined with each other under a certain mixed composition ratio. Therefore, these coatings
Not only does it have the excellent abrasion resistance and scuffing resistance inherent to ion plating coatings, but it also has excellent impact resistance and toughness, as well as high compactness and smoothness. Therefore, the sliding member of the present invention has very little surface chipping, peeling, breakage, etc. due to the excellent impact resistance and toughness of the coating, and the compatibility with the mating member due to wear due to the high density and smoothness of the coating. Is also very good.

Further, in the case of the above-mentioned ternary system ion plating film, metal Cr intervenes in the crystal grain boundary of the chromium nitride-containing ceramics, whereby the adhesive force between the crystal grains is strengthened. , The toughness of the ion plating film is further enhanced. Therefore, in the case of this ternary system, the number of surface defects, peeling, breakage, etc. is smaller than in the case of a binary system.

In the present invention, it is preferable to perform ion plating after nitriding the surface of the base material of the sliding member. In this case, the ion plating film is not directly formed on the base material, but is formed on the hard nitride layer covering the surface of the base material, and the ion plating film and the surface covered by the film are formed. The hardness difference is reduced. Therefore, the impact resistance of the ion plating film is further improved, and the chipping, peeling, breakage, etc. of the surface are reduced.

In the present invention, when the porosity of the ion plating film is set to 0.5 to 20.0%, the toughness can be increased without impairing the strength and wear resistance of the film, so that chipping and peeling are caused. Further, it is possible to exert a further effect in overcoming breakage and the like.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail by taking a vane for a rotary compressor as an example. However, the embodiment of the present invention is not limited to this, and sliding for a compressor is not limited thereto. It can be applied to all members.

1 to 4 show vanes 1 (1a to 1d) for a rotary compressor corresponding to the sliding member of the present invention. As shown in FIG. 5, these vanes 1
Are held in the vane groove 5 formed in the roller housing 10 of the rotary compressor via an elastic body such as a spring 7. And the roller 8 is the roller housing 1
With the eccentric rotation in 0, the nose portion of the vane 1 and the outer peripheral surface of the roller 8 slide, and the side surface portion of the vane 1 and the inner wall 6 of the vane groove slide.

Therefore, the vane 1 has two sliding surface regions, the nose portion and the side surface portion. In the case of FIG. 1 (vane 1a), the ion plating film is formed on the base material 2 at the nose portion and the side surface portion. 4 is directly formed and is shown in FIG. 2 (vane 1b).
In the case of, the ion plating film 4 was directly formed only on the base material 2 of the nose portion, and in the case of FIG. 3 (vane 1c), the nitride layer 3 and the ion plating were formed on the base material 2 of the nose portion and the side surface portion. 4 (vanes 1d), the nitride layer 3 is formed on the base material 2 in the nose portion and the side surface portion, and the ion plating is performed only on the nitride layer 3 in the nose portion. The coating film 4 is formed.

In the present invention, the forming material of the base material is not particularly limited, and conventionally used forming materials for sliding members can be generally used. The same applies to the case of the base material 2 of the vane 1 shown in the drawing, and an iron-based material, a graphite-based material, an iron-based sintered material, an aluminum-based material, a titanium-based material, or the like, which has been conventionally used as a material for forming a vane, is used. it can. Among these, iron-based materials are preferable, and high speed tool steel (for example, S
KH51) is particularly preferable.

On the sliding surface of the vane 1, a binary system or a ternary system consisting of CrN and Cr ₂ N or further containing metallic Cr is formed directly on the base material or via the nitride layer. A mixed ion plating film 4 is formed. This film 4
The mixed composition ratios of (1) CrN type chromium nitride in the case of binary system: 45.0 to 98.0 wt%, Cr ₂ N type chromium nitride: balance (2) CrN in the case of ternary system Type chromium nitride: 45.0 to 98.0% by weight, metallic Cr: 0.5 to 15.5% by weight, Cr ₂ N type chromium nitride: balance.

Table 1 shows CrN type chromium nitride and Cr.₂N type
The physical properties of chromium nitride are shown below. CrN and Cr₂N is excellent
It has abrasion resistance and scuffing resistance.
As you can see from the table, both are hard and brittle by themselves.
Yes. Therefore, CrN or Cr ₂Single component consisting of only N
When using the ion plating film of
Also, in the case of
Chipping and peeling often occur, resulting in a significant decrease in the yield rate.
You. In addition, the obtained finished product is used by incorporating it in the compressor.
Extremely strong against dynamic and thermal shocks during operation
Since it is weak, it is easy to cause breakage etc.
Wear resistance and
The scuffing property cannot be fully utilized.

[0023]

[Table 1] On the other hand, in the mixed ion plating film used in the present invention, two chromium nitrides having different properties have different crystal systems (CrN is cubic crystal and Cr ₂ N is hexagonal crystal). It has been produced by being entangled in a complicated manner and is entangled in a complicated manner, and has excellent impact resistance and toughness, and is extremely dense and smooth. Moreover, this coating has a relatively low hardness and elastic modulus between the two chromium nitrides, and a C having relatively poor wear resistance and coating adhesion.
Although it is a mixture with r ₂ N, since the mixture composition ratio of both chromium nitrides is appropriately adjusted, impact resistance without causing deterioration of wear resistance and coating adhesion due to Cr ₂ N,
The toughness, denseness, and smoothness are improved.

Therefore, according to the present invention, it is possible to obtain a sliding member which is excellent not only in abrasion resistance and scuffing resistance but also in impact resistance and compatibility with the mating member. it can. That is, according to the present invention, among CrN and Cr ₂ N, the wear resistance and scuffing resistance equal to or higher than those of the ion plating film made of CrN alone, which has particularly excellent wear resistance and scuffing resistance, are maintained. It is possible to improve impact resistance and toughness as it is, and by doing so, it is possible to overcome chipping, peeling, breakage and the like of the sliding member. At the same time, by improving the compactness and the smoothness, it is possible to weaken the mating member aggression of the sliding member and significantly reduce the amount of wear of the mating member. For example, FIG.
With the vane 1 inside, it is possible to suppress the wear of the mating member such as the outer peripheral surface of the roller 8 and the inner wall 6 of the vane groove.

In the present invention, the proportion of CrN-type chromium nitride in the ion plating film has a lower limit value of 45.0% by weight, preferably 55% by weight, and an upper limit value of 98.0% by weight, preferably 88% by weight. Here, when the composition ratio of CrN is less than 45.0% by weight, Cr ₂ N, which has relatively lower wear resistance and film adhesion than CrN, becomes too much. The wear resistance and coating adhesion of the coating drop sharply. On the other hand, even if the CrN ratio exceeds 98.0% by weight, a sharp increase in wear resistance or film adhesion cannot be expected.

The sliding member of the present invention includes CrN and Cr ₂ N.
In addition to the above, a ternary mixed ion plating film containing metal Cr may be further formed. In the case of this ternary mixed coating, metal Cr intervenes in the crystal grain boundary of the ceramic containing two types of chromium nitrides, CrN and Cr ₂ N, which strengthens the adhesive force between the crystal grains. Therefore, the toughness of the ion plating film is further enhanced. Therefore, in the case of this ternary system, chipping, peeling, breakage, etc. of the sliding member are further reduced as compared with the case of the binary system. The lower limit of the mixed composition ratio of metallic Cr is 0.
5% by weight, preferably 5% by weight, the upper limit of which is 1
It is set to 5.5% by weight, preferably 10% by weight. Metal Cr
If the ratio is less than 0.5% by weight, there is no effect. On the other hand, if the ratio exceeds 15.5% by weight, the scuffing resistance is rather lowered.

Since the toughness of the ion plating film also changes depending on the porosity of the film, it is possible to further reduce chipping, peeling, breakage and the like by appropriately adjusting the porosity to increase the toughness. From this point of view, in the present invention, the lower limit of the porosity of the ion plating film,
It is preferably 0.5%, particularly preferably 5%, and its upper limit value is preferably 20.0%, particularly preferably 15%.
And When the porosity is less than 0.5%, the denseness of the film is high and the film is brittle, so that chipping, peeling and the like are likely to occur. On the other hand, when the porosity is more than 20.0%, the strength of the ion plating film itself is reduced and it tends to be corroded, so that the wear resistance is likely to be reduced.

In the present invention, the method for forming the ion plating film is not particularly limited. As an example, for example,
The ion plating film can be formed by the following method. That is, first, the base material with or without the nitride layer is placed in a vacuum chamber. If there is a nitride layer, the compound layer on the top of the nitride layer may be removed prior to forming the ion plating film. Next, the base material temperature is usually controlled to about 200 to 600 ° C., nitrogen gas is introduced as a reaction gas, Cr is evaporated in the reaction gas atmosphere, and then ionized. Then, on the negatively biased surface of the base material, a reaction product of the reaction gas and ionized Cr (that is, CrN,
By forming Cr ₂ N), an ion plating film can be formed. In this case, CrN and Cr ₂ N or CrN and Cr ₂ N present in the film
The mixed composition ratio of Cr and Cr can be adjusted by changing the gas pressure of nitrogen gas which is a reaction gas.

The hardness of the ion plating film 4 thus formed is Vickers hardness Hv1800 or more. The thickness of the film 4 is usually 2 μm or more,
It is preferably at least 5 μm.

In the present invention, the ion plating film may be formed directly on the base material, but the surface of the base material is nitrided like the illustrated vane 1c (FIG. 3) and vane 1d (FIG. 4). After that, it is preferable to form an ion plating film through the nitride layer 3. When the ion plating film 4 is formed on the nitride layer 3 having a hardness higher than that of the base material 2, the difference in hardness between the ion plating film and the surface covered by the film is reduced. Therefore, the impact resistance of the ion plating film is further improved, and the occurrence of chipping, peeling, breakage, cracks, etc. on the surface is reduced.

The method for forming the nitride layer 3 is not particularly limited, and an ion nitriding method such as ion pure nitriding or ion soft nitriding, or a gas nitriding method can be appropriately adopted. For example, in the case of the ion pure nitriding treatment, the base material 2 is degreased and washed, and then preheated, and the heated base material 2 is pressed at a pressure of 0.5 to 10 to.
Place in a closed container having a (H ₂ + N ₂ ) gas atmosphere or NH ₃ gas atmosphere of about rr. Then, a voltage of 100 to 500 V is applied using the base material 2 as a cathode and the closed container as an anode, and ionized nitrogen generated by glow discharge generated at this time and the base material 2 are heated to cause nitriding.

In the case of the ion soft nitriding treatment, the (H ₂ + N ₂ ) gas atmosphere or the NH ₃ gas atmosphere in the above-mentioned ion pure nitriding treatment is changed to the (N ₂ + C ₃ H ₈ ) gas atmosphere or (C _The atmosphere may be replaced by a hydrocarbon-based gas such as ₄ H ₁₀ , C ₂ H ₂ and CH ₄ .

The surface hardness of the nitride layer 3 thus formed is Vickers hardness Hv1200 or more. Regarding the thickness of the nitride layer 3, the thickness of the compound layer is usually 1 μm or more, preferably 5 μm or more, and the thickness of the diffusion layer is usually 40 μm or more, preferably 50 μm or more.

In the present invention, it is not necessary to form the ion plating film on the entire surface of the sliding member, it is sufficient to form the ion plating film only on the area of the sliding surface, and the sliding surface is formed on the sliding member. In the case of a plurality of layers, the ion plating film may be formed only on the sliding surface that requires it. The same applies to the nitride layer interposed between the surface of the base material and the ion plating film, and it is not necessary to form it on the entire surface of the sliding member. As described above, when the ion plating film or the nitride layer is locally formed, the production efficiency is improved as compared with the case where the ion plating film and the nitride layer are entirely formed, and thus the cost can be reduced.

For example, in the case of the vane 1a shown in FIG. 1 (FIG. 1), there is no coating on the tip of the base side, which is not the sliding surface, and there is an ion plating coating on the two sliding surfaces, the nose and the side. 4 are formed. On the other hand, in the case of the vane 1b (FIG. 2), the ion plating film 4 is formed only on the nose portion of the two sliding surfaces. Although FIGS. 3 and 4 show the case where there is a nitride layer, in the case of the vane 1c (FIG. 3), the nitride layer 3 and the ion plating film 4 are sequentially formed on the nose portion and the side surface portion. On the other hand, in the case of the vane 1d (FIG. 4), the nitride layer 3 is formed on the two sliding surfaces,
The ion plating film 4 is formed only on the nose portion of the two sliding surfaces which is exposed to particularly severe sliding conditions.

[0036]

【Example】

Next, an experimental example of the present invention will be shown. Experimental Example 1 A sliding member for a compressor was tested for wear resistance and opponent attack using an Amsler type tester. A doughnut-shaped (outer diameter 40 mm, inner diameter 16 mm, thickness 10 mm) high-speed tool steel (SKH51) was used as the base material, and various surface treatments described below were applied to the outer peripheral surface of the test piece (sample, Comparative samples 1-2) were prepared. On the other hand, as a mating material for the test piece, a flat plate (18
mm × 15 mm × thickness 5 mm) monichrome (cast iron containing molybdenum, nickel and chromium) was used. Then, as shown in FIG. 6, a doughnut-shaped test piece was used as a rotating piece 23 in a plane contact sliding wear test, and this was dipped in the lubricating oil 22 stored in the container 21, while the flat plate-shaped mating member was fixed. It was used as a piece 24, and this was pressed against a rotating piece (test piece) by applying a load P to rotate the rotating piece 23. Details of the test conditions and test pieces are as follows.

[Test Conditions] Tester: Amsler type tester Rotating piece: donut-shaped (outer diameter 40 mm, inner diameter 16 mm, thickness 10 mm) and comparative samples 1-2 Fixed piece: flat plate (18 mm × 15 mm × thickness) 5 mm) rotation speed: 1 m / sec (478 rpm) Lubricating oil: Ester oil Oil temperature: 75 ° C Load: 100 kg Hour: 7 hours [Details of test piece] Test piece (sample and comparison 1-2) were produced as follows.

(1) Sample After high-speed doughnut-shaped high speed tool steel (SKH51) was preheated at 430 ° C. for 2 hours, gas pressure was 4 torr, N ₂ gas and H ₂ were added.
Mixing ratio with gas N ₂ : H ₂ = 7: 3, temperature 520 ° C.
Ion pure nitriding treatment was performed for 30 minutes under the conditions described above to form a nitride layer on the surface of the base material. This nitrided layer had a compound layer with a thickness of 5 μm and a diffusion layer with a thickness of 80 μm below it, and had a surface hardness of Hv1200.

Then, an ion plating film was formed by a reactive ion plating method on the nitride layer on the outer peripheral surface of the doughnut-shaped base material. That is, Cr is vaporized in a reaction gas such as nitrogen, ionized in a vapor phase state, and CrN-type chromium nitride and Cr, which are reaction products of the reaction gas and vaporized material ions, are formed on the surface of the base material that is negatively biased. _{2 An} ion plating film made of a mixture with N-type chromium nitride was formed.

The sample manufactured in this manner was obtained by forming a nitride layer and a Cr film having a thickness of 4 μm on the base material SKH51.
Mixed ion plating film of N type chromium nitride and Cr ₂ N type chromium nitride (mixed composition ratio is CrN: Cr ₂ N =
50:50) were sequentially formed.

(2) Comparative 1 Nitriding was performed in the same manner as in the case of the sample, and then the reactive ion plating method was applied on the nitride layer on the outer peripheral surface of the base material having a donut shape to obtain only CrN-type chromium nitride. An ion plating film of was formed.

In Comparative Example 1 produced in this way, a nitride layer and a 4 μm thick CrN film were formed on the base material SKH51.
The ion plating film consisting of only chromium nitride was sequentially formed.

(3) Comparative 2 Nitriding was performed in the same manner as in Comparative 1, and then the reactive ion plating method was applied to the nitride layer on the outer peripheral surface of the base material having a donut shape to form Cr ₂ N type. An ion plating film made of only chromium nitride was formed.

In Comparative Example 2 thus produced, a nitride layer and a Cr ₂ film having a thickness of 4 μm were formed on the base material SKH51.
The ion plating film consisting only of N-type chromium nitride was sequentially formed.

[Results] The test results are shown in FIG. Cr ₂ N
In the case of Comparative 2 having a single ion plating film, the wear amount of self is 1.5 μm and the wear amount of the mating material is 1.1 μm, which does not have sufficient wear resistance and also has aggression property against the mating material. high. Further, in the case of Comparative 1 having the ion plating film of CrN alone, the wear amount of self is 0.4.
[mu] m, the wear amount of the mating member is 0 .mu.m, the abrasion resistance is somewhat improved if compared to the Cr ₂ N alone, has fallen counterpart material. A sample having a mixed ion plating film of CrN and Cr ₂ N as compared with these (invention product)
Indicates that the wear amount of self is 0.2 μm and the wear amount of the mating material is 0 μm.
It is found that the abrasion resistance is remarkably improved.

Experimental Example 2 Next, in order to confirm the superiority of the sliding member of the present invention, various surface treatments were performed on a high-speed tool steel (SKH51) which is a base material, and test pieces (Sample 1 to Sample 1). 6, comparative sample 1
To 3) were prepared and tested for abrasion resistance, scuffing resistance and adhesion (peelability).

For the test piece of Experimental Example 2, the same doughnut-shaped high-speed tool steel as that of Experimental Example 1 (having the same shape and size) was used, and nitriding and ion plating were performed in the same manner as in Experimental Example 1. It was made by.

Each test piece produced in this way is
As shown in Table 2, a nitride layer and a mixed or single ion plating film having a thickness of 4 μm were sequentially formed on the base material SKH51.

[0049]

[Table 2] * 1 Composition: Determined by the reflection intensity ratio of each composition in the X-ray analysis pattern * 2 Porosity: Calculated from image processing of the cross-section cut microscopic sample surface (1) Wear resistance test Same as Experimental Example 1 The abrasion amount of each test piece (rotating piece) and the mating material (fixed piece) was measured by operating the above. The results are shown in Fig. 8. When the wear amount of the conventional test piece having the ion plating film of CrN alone (Comparative Sample 3) is 100, the wear index of Samples 1 to 5 itself is 50, which is excellent in wear resistance. The wear index of the material is 40, which shows that the opponent's aggressiveness is also low.

The content of CrN is lower than that of the product of the present invention (4
0% by weight) Comparative sample 1 and sample 6 of the present invention, which has a large porosity (25%), have a wear index of 95 and 85, respectively, and a wear index of the mating material of 8 respectively.
The values were 0 and 70, which were slightly better than those of CrN alone. Comparative sample 2 containing too much Cr (20% by weight) had a wear index of 80 and a wear index of the mating material of 70.
And there was little improvement.

(2) Scuffing resistance test This test was conducted basically in the same manner as the wear resistance of Experimental Example 1. That is, using an Amsler type tester, doughnut-shaped (outer diameter 40 mm, inner diameter 16 mm, thickness 10 mm) samples 1 to 6 and comparative samples 1 to 3 were used as test pieces (rotating pieces), and flat plates ( 18 mm x
A 15 mm × 5 mm thick monichrome was used. And
First, in order to adjust the sliding surfaces of the rotary piece and the fixed piece to each other, a load of 25 kg / cm ² was applied to press the fixed piece against the rotary piece, and the lubricating piece was rotated for 20 minutes while supplying the lubricating oil. Next, the surface pressure was increased to 30 kg / cm ² , and then 5 minutes every 2 minutes.
The scuffing was finally caused by increasing in kg / cm ² , and the load when the scuffing occurred was measured as the limit surface pressure. The test conditions are shown below.

[Test Conditions] Testing machine: Amsler type testing machine Rotating piece: Donut-shaped (outer diameter 40 mm, inner diameter 16 mm, thickness 10 mm) Samples 1 to 6 and comparative samples 1 to 3 Fixed piece: flat plate (18 mm x 15mm x 5mm thick) Monikuro Rotational speed: 5m / sec Lubricating oil: SAE30 + white kerosene (1: 1) Oil temperature: 50 ° C Oil amount: 0.2 liter / min Load: 25kg / cm ² for 20 minutes After that, 30 kg /
cm ² and thereafter successively increases by 5 kg / cm ² every 2 minutes until scuffing occurs. The test results are shown in FIG. 9 with the critical surface pressure of CrN alone (Comparative Sample 3) set to 100. As shown in FIG. 9, the limit surface pressure of the test piece (comparative sample 3) having the conventional ion plating film of CrN alone is set to be 1
When set to 00, the indices of Samples 1 to 5 are 300, which shows that the scuffing resistance is excellent.

The indices of Comparative Sample 1, Comparative Sample 2, and Sample 6 are 150, 135, and 12, respectively.
5 was about half of Samples 1-5. (3) Adhesion test (scratch test) A critical load related to the adhesion and durability of the ion plating film was measured by a scratch test. The test result shows that the critical load of CrN alone (Comparative sample 3) is 1
00 is shown in FIG. As shown in FIG. 10, when the peeling index of the test piece (comparative sample 3) having the conventional ion plating film of CrN alone is 100, the indexes of Samples 1 to 6 are 100 to 130, and C is
It was equal to or better than rN alone.

Comparative Sample 1 was inferior in peelability to CrN alone. The index of comparative sample 2 is 120
Although it is excellent in peeling property, it is not suitable for use because it does not have the abrasion resistance of FIG. 8 and the scuffing resistance of FIG. 9 at the same time as described above.

[0055]

As described above, the sliding member for a compressor of the present invention retains the wear resistance and scuffing resistance equivalent to or higher than those when the conventional ion plating film is used. In addition to excellent chipping, peeling, breakage, cracks, etc., it has excellent processability during manufacturing and durability during operation. can do.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an example (1a) of a vane for a rotary compressor according to the present invention.

FIG. 2 is a vertical sectional view of an example (1b) of a vane for a rotary compressor according to the present invention.

FIG. 3 is a vertical cross-sectional view of an example (1c) of a vane for a rotary compressor according to the present invention.

FIG. 4 is a vertical sectional view of an example (1d) of a vane for a rotary compressor according to the present invention.

FIG. 5 is an explanatory diagram showing a rotary compressor using a vane for a rotary compressor according to the present invention.

FIG. 6 is an explanatory diagram showing an outline of an Amsler type testing machine.

FIG. 7 shows the results of the abrasion resistance test conducted in Experimental Example 1.

FIG. 8 is a result of an abrasion resistance test conducted in Experimental Example 2.

9 is a result of a scuffing resistance test conducted in Experimental Example 2. FIG.

FIG. 10 is a result of a scratch test performed in Experimental Example 2.

[Explanation of symbols]

 1 (1a-1d) ... Vane 2 ... Base material 3 ... Nitride layer 4 ... Ion plating film 5 ... Vane groove 6 ... Vane groove inner wall 7 ... Spring 8 ... Roller 9 ... Shaft 10 ... Roller housing 21 ... Container 22 ... Lubricating oil 23 ... Rotating piece (test piece) 24 ... Fixed piece (counterpart) P ... Load

Claims (5)

[Claims] 1. A sliding member for a compressor, which relatively slides in a compressor, comprising a mixture of CrN-type chromium nitride and Cr ₂ N-type chromium nitride in at least one sliding surface region thereof. Ion plating film is formed,
The mixed composition ratio of the ion plating film is CrN-type chromium nitride: 45.0 to 98.0% by weight, and Cr ₂ N
Type Chromium Nitride: A sliding member for a compressor, characterized by the balance. 2. A nitride layer is formed on a base material in at least one sliding surface region of a compressor sliding member, and the ion plating film is formed on the nitride layer. The sliding member for a compressor according to claim 1. 3. A sliding member for a compressor which relatively slides in a compressor, wherein CrN-type chromium nitride, Cr ₂ N-type chromium nitride and metallic Cr are present in at least one sliding surface region thereof.
And an ion plating film made of a mixture thereof with a mixed composition ratio of CrN-type chromium nitride: 45.0 to 98.0% by weight, C
r: 0.5 to 15.5% by weight, and Cr ₂ N-type chromium nitride: the balance, a sliding member for a compressor. 4. A nitride layer is formed on a base material in at least one sliding surface region of a compressor sliding member, and the ion plating film is formed on the nitride layer. The sliding member for a compressor according to claim 3. 5. The porosity of the ion plating film is 0.5 to 20.0%.
5. The sliding member for a compressor according to any one of 4 to 4.