JPH05171376A - Material for vane, vane and manufacture of vane - Google Patents

Abstract

PURPOSE:To provide the method for manufacturing the material for a vane and a vane used for a compressor using alternative fluorocarbon as a refrigerant and improving its wear resistance. CONSTITUTION:This is the material for a vane and a vane having a compsn. contg. 1.0 to 2.5% C, b <=1.5% Si, <=1.0% Mn, 3 to 6% Cr, one or two kinds of <=20% W and <=2% Mo of 15 to 28% W+2Mo and 3.5 to 10% of one or two kinds of V and Nb and contg., at need, 1 to 15% of one or two kinds of Co and Ni, and the balance Fe with inevitable impurities, and in which carbides are uniformly dispersed into a matrix, the average grain size is regulated to <=1.5mum and the maximum grain size is regulated to <=6mum, and this is their manufacturing method in which atomizing powder having the compsn. is compacted and is thereafter subjected to hot working or hot working and cold working.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vane used in a compressor such as a rotary compressor and a vane pump.

[0002]

2. Description of the Related Art As shown in FIG. 1, an example of a compressor using a vane, a vane 1 has a spring 4 and a rotor 2 at all times.
Is pressed against the eccentric rotation of the rotor 2,
The gas is compressed by the volume change of the space formed by the rotor 2 and the cylinder 3. Conventionally, Freon gas has been used as the refrigerant gas. Since the tip of the vane is always in contact with the rotor and the side surface of the vane is in contact with the cylinder, the characteristic required for the vane is that the vane itself does not wear and at the same time the other rotor or cylinder does not wear. is there. Conventionally, a molten high speed steel corresponding to SKH51 type has been generally used for this vane, and a part of this has been subjected to a surface treatment such as oxynitriding. Further, for the purpose of improving the material and composition of the vane, improving wear resistance, and improving self-lubricating property, JP-A-56-47550.
No. 59-20446 and 61-4855.
6, JP-A-64-35091, JP-A-2-1023.
The one described in No. 92 has been proposed.

[0003]

The refrigerant used in the above-mentioned compressor is a chlorofluorocarbon (hereinafter referred to as CFC).
The CFC diffuses into the stratosphere and then decomposes upon exposure to ultraviolet rays to release chlorine, thereby destroying the ozone layer. For this reason, CFC is planned to be completely abolished by the year 2000, and development of a refrigerant agent to replace it is in progress. As an alternative refrigerant, hydrofluorocarbon (hereinafter referred to as HFC) -based CFC containing no chlorine is the most promising, and this type of CFC has little environmental damage. However, the vane pump and the rotary compressor using HFC-based CFCs have the following problems as compared with the conventional CFC-based CFCs. The lubricity of the refrigerant is poor. It is necessary to increase the compression ratio, which increases the load on the vanes. The hygroscopicity of the refrigerant is high. The lubricity of lubricating oil is inferior. The hygroscopicity of the lubricating oil increases.

Due to the above-mentioned causes, sliding wear with the rotor is extremely accelerated in the conventional vane, and if it is excessive, it may cause galling with the rotor, so that the practical life of the compressor cannot be obtained. It has become clear. An object of the present invention is to provide a novel vane material mainly used in a compressor using HFC-based CFC as a refrigerant, a vane and a method for producing the vane.

[0005]

The first aspect of the present invention is, in terms of weight%, C 1.0 to 2.5%, Si 1.5% or less, Mn 1.0% or less, Cr 3 to 6%, W 20% or less, Mo. 1% or less of 12% or less contains 15 to 28% in W + 2Mo, 3.5% to 10% of 1 or 2 types of V and Nb, and consists of the composition of the balance Fe and unavoidable impurities. Is uniformly dispersed, and the average particle size is 1.5 μm or less and the maximum particle size is 6 μm or less. A vane material is characterized in that the second invention is C 1.0 to 2.5% by weight and Si 1.5 % Or less, Mn 1.0% or less, Cr 3 to 6
%, W 20% or less, Mo 12% or less 1 type or 2 types W +
15 to 28% at 2 Mo, 3.5 to 10% of one or two kinds of V and Nb,
It contains 1 to 15% of Co and Ni in total of 1 to 15% and consists of the composition of balance Fe and unavoidable impurities. Carbides are uniformly dispersed in the matrix, and the average particle size is 1.5 μm or less, the maximum. A vane material having a particle size of 6 μm or less. The third invention is such that the range of each element is the most desirable range, and C 2.0 to 2.5% by weight% and Si 0.1 to 0.6% by weight.
%, Mn 0.1 to 0.6% or less, Cr 3 to 6%, W 20% or less, Mo
1 or 2 of 12% or less is 17 to 26% at W + 2Mo, V,
6-10% of one or two of Nb, one or two of Co, Ni
The total amount of seeds is 7 to 12%, the balance is Fe and the composition of unavoidable impurities, the carbide is uniformly dispersed in the matrix, and the average particle size is 1.5 μm or less and the maximum particle size is 6 μm or less. It is a material for vanes characterized by. A fourth invention is the vane material according to the first to third inventions, wherein the area ratio of the MC type carbide dispersed in the matrix is 15% or more, and the fifth invention is
The present invention is a vane having the composition according to any one of the first to fourth inventions, and the sixth invention is the first to fourth inventions.
A vane according to any one of the inventions, characterized in that it has a hardening treatment layer on at least the sliding surface.
The present invention is a vane characterized by having a cured coating layer on at least the sliding surface of the vane according to any one of the first to fourth inventions, and the eighth invention is the vane according to the first to fourth inventions.
In the method for producing a vane, characterized in that after atomizing an atomized powder having a composition according to any one of the inventions, it is produced by hot working or hot working and cold working, and that it has substantially no pores. is there.

[0006]

The function of each element and the reason for limiting the numerical values in the present invention will be described below. C is added at the same time W, M
Combined with o, V, etc., it forms hard carbides, has the effect of increasing wear resistance and reducing galling with the mating material. Also,
Some of them also form a solid solution in the matrix to increase the hardness of the matrix and also have the effect of improving wear resistance. Therefore, there is an optimum C content in consideration of the addition amounts of carbide forming elements such as W, Mo, and V. In the range of the present invention, when C is less than 1.0%, the hardness of the matrix is not sufficiently obtained, and the amount of carbide formed is small. Conversely 2.
If it exceeds 5%, the toughness deteriorates and the hot workability becomes difficult, so C is set to 1.0 to 2.5%. The range of C that gives the best characteristics is 2.0 to 2.5%.

Si has the effect of improving the steel quality as a deoxidizing element. It also has the effect of increasing the hardness of the base by forming a solid solution in the base. However, if it exceeds 1.5%, the toughness decreases, so Si was made 1.5% or less. Desirable range of Si is 0.1-0.6%
Is. Since Mn also has an effect of improving the steel quality as a deoxidizing element, Mn is set to 1.0% or less. The desirable range of Mn is 0.1
~ 0.6%.

Cr has the effect of forming carbides and increasing wear resistance. Furthermore, it forms a solid solution in the substrate to give hardenability,
It also improves the corrosion resistance of the base. Particularly in the present invention, the vane operates in a weak corrosive environment because the alternative CFC HFC has high hygroscopicity and the lubricating oil decomposes to form an acid such as a carboxylic acid. Therefore, it is estimated that the abnormal wear on the vanes is caused not only by simple abrasive wear but also by a mechanism involving corrosion. In this case, in addition to Cr, the solid solution of Mo, Co, and Ni, which will be described later, to the base has the effect of increasing the corrosion resistance of the vane and reducing wear. If the Cr content is less than 3%, the above-mentioned effect is small. On the contrary, if the Cr content exceeds 6%, it becomes difficult to obtain hardness by heat treatment.
It was 6%.

W and Mo combine with C to form an M ₆ C type carbide, which enhances wear resistance and galling resistance. In addition, it has the effect of increasing the hardness of the matrix by solidifying it in the matrix and then precipitating and hardening it by tempering. Mo also has the effect of suppressing corrosion due to carboxylic acid. Mo is twice as effective as W. One or two with W 20% or less and Mo 12% or less is W + 2
If the Mo content is less than 15%, the above effect is small, and if it exceeds 28%, toughness decreases and hot workability also decreases, so W + 2
The Mo was set to 15 to 28%. Desirable range of W + 2Mo is 17-26
%.

V and Nb are elements that have an important effect in the present invention. That is, V and Nb combine with C to form MC type carbides. When this carbide is finely and uniformly dispersed on the surface of the vane, the wear of the vane is reduced and the wear of the rotor of the other party can be suppressed. Depending on the structure of the compressor, the material of the mating rotor, and the number of required lives, it is possible to add the characteristics required as a vane for CFC alternatives for HFCs with one or two of V and Nb at 3.5% or more. However, the effect becomes remarkable especially when 6% or more is added. If it is less than 3.5%, the above effect is not sufficient, and if it exceeds 10%, atomization is difficult,
Due to the difficulty of hot working, the content of one or two of V and Nb was set to 3.5 to 10%.

Co and Ni form a solid solution in the matrix and have a high effect of suppressing the corrosion due to the carboxylic acid which is important in the present invention. That is, as described above, when an alternative CFC such as HFC is used as a refrigerant, corrosive wear also occurs and abnormal wear of the vane occurs, but one or two of Co and Ni in total is 1 to 1
Abnormal wear can be reduced by making 5% solid solution in the base,
Especially when it is 7% or more, curing is large. However, if it exceeds 12%, the toughness decreases, so the upper limit was made 12%. Also, Co has the effect of increasing the hardness of the base to suppress the wear of the vanes, and further has the effect of suppressing galling with the mating rotor.

The vane functions as a compressor while sliding on the rotor and the cylinder. When the conventionally known high V type high speed steel or high Co type high speed steel is used as the vane material, the wear resistance of the vane is improved. However, since the size of the carbide particles forming the microstructure is large, the other rotor or cylinder is attacked and extremely worn, which is not suitable as a vane material. In order to solve this, it has been found in the present invention that the diameter of the carbide particles forming the microstructure of the vane should be made fine enough not to attack the mating rotor or cylinder. Specifically, it is necessary that the average particle diameter of the carbide is 1.5 μm or less and the largest carbide diameter is 6 μm or less. If it is larger than this, the vane wears less, but the rotor and the cylinder wear more, and the compression capacity decreases.

Further, among the carbides forming the microstructure of the vane, it has been found that especially MC type carbides not only suppress the wear of the vane but also suppress the wear of the mating rotor and the cylinder. If the area ratio of the MC-type carbide dispersed is less than 15%, the effect is small. Therefore, the area ratio of the MC-type carbide dispersed is limited to 15% or more. In order to finely and uniformly disperse the carbide of the vane material, after atomizing the atomized powder of the above composition using HIP or the like, hot working and further cold working as necessary, a flattened shape close to the cross-sectional shape of the vane is used. It is best to manufacture square steel and use it as a vane. According to this method, as compared with the melting method, a vane material having a fine metal structure can be obtained, and since there are no defects such as microvoids peculiar to the sintering method, variations in quality are small and effective. When the vane manufactured by using the above-mentioned vane material is hardened on the surface such as nitriding, sulfuritriding, and oxynitriding, or subjected to a treatment for increasing the area ratio of dispersed particles such as nitride, the life of the vane and the rotor is shortened. Further improve.
In addition, even if a hard and friction-reducing film such as a TiN or Ni-P composite film is coated, the life of the vane and the rotor is significantly improved.

[0014]

EXAMPLES Examples will be shown below. (Example 1) Ten kinds of vane materials shown in Table 1 were prepared. Among these, the materials of the present invention, AI and K
For M, a gas atomized powder was canned, then consolidated by HIP, and made into a rectangular steel by hot forging and hot rolling. Conventional material J is conventional high speed tool steel SKH51,
A steel ingot melted and ingot in the air was similarly hot-forged and hot-rolled into a rectangular steel. Table 2 shows the quenching-tempering hardness (HRC) of the vane material shown in Table 1, the area ratio and average particle size and maximum particle size of the carbide contained in the steel material in this state, the wear reduction by the wear test, The corrosion weight loss by the corrosion test is shown respectively. Incidentally. The abrasion test was carried out as follows. FC2 equivalent to rotor material with vane material in plate shape
HF, which is a representative of HFC Freon, has a ring shape of 5.
The ester-based lubricating oil compatible with C134a was dropped and slid on each other to determine the wear reduction. In Table 2, the wear amount of each vane material and the ring at that time was obtained as a relative comparison value, and the wear amount of each of the plate and the ring when tested by using the conventional material SKH51 as the plate and FC25 as the ring was set to 1.0 and evaluated. did.

[0015]

[Table 1]

[0016]

[Table 2]

(Example 2) Using the materials of symbols C, H, and K shown in Table 1, a test piece for the same wear test as in Example 1 was prepared, and then the friction surface thereof was nitrided and sulfuritrided. , Oxynitriding treatment was performed. In another test piece, a TiN film was formed by physical vapor deposition and a Ni-P-SiC composite plating film was formed by plating. A wear test and a corrosion test were performed under the same conditions as in Example 1 using these test pieces. The results are shown in Table 3. According to Table 3, by subjecting the vane material of the present invention to the surface hardening treatment or the hard film coating treatment, the wear of the vane and the mating material can be significantly reduced.

[0018]

[Table 3]

Example 3 A vane was actually produced by using the material of the symbols A and H shown in Table 1 and SKH51 (symbol J) which is a conventional molten high speed tool steel, and HFC1 was used.
A life evaluation test was carried out by incorporating it into an actual rotary compressor using 34a as a refrigerant. In the evaluation during the actual machine test, the vane wear or damage was estimated by the pressure change of the pressure gauge installed in the rotary compressor. As a result of the actual machine test, the pressure of the test machine using the conventional material SKH51 for the vane suddenly changed 125 hours after the start of the operation, so the operation was stopped and the condition of the vane was observed. As a result, the SKH51 vanes were partially scratched on the surface sliding with the rotor, while scratches were also observed on the opposing rotor peripheral surface. On the other hand, in the rotary compressor using the vanes made of the symbols A and H of the present invention, the pressure change was not observed even after 720 hours of operation, and the test was stopped.

[0020]

EFFECTS OF THE INVENTION According to the present invention, in a compressor using an alternative CFC represented by HFC type CFC as a refrigerant, the wear resistance of the vane, which has been insufficient in the conventional vane material SKH51 class, is significantly improved. improves. Further, the vane of the present invention not only has a great effect of suppressing wear and galling of the counterpart material such as the rotor and cylinder by increasing the area ratio in which carbides are finely and uniformly dispersed or MC type carbides are dispersed, but also HFC-based flon is used. Corrosion resistance is high against acids such as carboxylic acids formed by decomposition of lubricating oil for compressors.
Further, by providing a surface hardening treatment layer or a hard coating treatment layer on at least the sliding surface of the vane, a compressor having a longer life can be obtained. Therefore, the vane of the present invention can be applied to a new refrigerant due to its large wear resistance and corrosion resistance, so that a compressor that meets environmental regulations can be put to practical use.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a rotary compressor.

[Explanation of symbols]

 1 vane 2 rotor 3 cylinder 4 spring

Claims (8)

[Claims] 1. C 1.0 to 2.5% by weight, Si 1.5% or less,
Mn 1.0% or less, Cr 3 to 6%, W 20% or less, Mo 12% or less 1 type or 2 types and W + 2 Mo 15 to 28%, V or Nb 1 type or 2 types 3.5 to 10%. A vane material which contains the balance Fe and unavoidable impurities, and has carbides uniformly dispersed in the matrix and having an average particle size of 1.5 μm or less and a maximum particle size of 6 μm or less. 2. C 1.0 to 2.5% by weight, Si 1.5% or less,
Mn 1.0% or less, Cr 3 to 6%, W 20% or less, Mo 12% or less 1 type or 2 types, W + 2Mo 15 to 28%, V or Nb 1 type or 2 types 3.5 to 10%, 1 or 2 types of Co and Ni
It contains 15% and consists of the composition of balance Fe and unavoidable impurities. Carbides are uniformly dispersed in the matrix, and the average particle size is 1.
A vane material having a maximum particle size of 5 μm or less and a maximum particle size of 6 μm or less. 3. C 2.0-2.5% by weight, Si 0.1-0.6
%, Mn 0.1 to 0.6%, Cr 3 to 6%, W 20% or less, Mo 12%
The following 1 or 2 contains 17 to 26% of W + 2Mo, 6 to 10% of 1 or 2 of V and Nb, and 7 to 12% of 1 or 2 of Co and Ni, and the balance A vane material comprising Fe and unavoidable impurities, in which carbides are uniformly dispersed in the matrix, and the average particle size is 1.5 μm or less and the maximum particle size is 6 μm or less. 4. The vane material according to claim 1, wherein the area ratio of the MC-type carbide dispersed in the matrix is 15% or more. 5. A vane made of the material according to any one of claims 1 to 4. 6. The vane according to claim 1, which has a hardening treatment layer on at least the sliding surface. 7. The vane according to claim 1, wherein at least the sliding surface has a cured coating layer. 8. Atomized powder having the composition according to any one of claims 1 to 4 is manufactured by hot working or hot working and cold working after consolidation and is substantially void-free. A method for producing a characteristic vane.