JP2000283072A - Compressor vane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the swelling or chipping of a corner part by forming an ion plating layer consisting of a mixture of Cr2N type chromium nitride and CrN type chromium nitride on the sliding surface of a base material consisting of high-speed tool steel (SKH51) directly or through an undercoat. SOLUTION: As the base material 2 of a vane 1, quenched and tempered high-speed tool steel (SKH51) is used. An ion plating layer 3 consisting of a mixture of Cr2N type chromium nitride and CrN type chromium nitride is formed on the sliding surface of the base material 2. The thickness of the ion plating layer 3 is set to the largest 4-11 μm in a top end surface 5, 3-7 μm slightly smaller than it on both surfaces 6, and the smallest 1-5 μm on both side surfaces. According to this, since the sliding part of the vane 1 is covered with the ion plating layer 3, the wear resistance and the wear compatibility with a counter member can be improved. Thus, the swelling or chipping of the corner part of the vane 1 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a compressor vane having an ion plating layer formed on a sliding surface of a base material.

[0002]

2. Description of the Related Art A sliding member for a compressor, such as a vane for a compressor, has a sufficient abrasion resistance and impact resistance on a sliding surface, and the occurrence of peeling and cracks is suppressed. It is desirable to form a coating layer that is also excellent in abrasion compatibility. As such a sliding member for a compressor, JP-A-7-286589
No. 1 forms a nitrided layer on a base material, and a Cr layer is formed on the nitrided layer.
It discloses an ion plating layer in which 2N-type chromium nitride and CrN-type chromium nitride are mixed.

[0003]

However, when a nitriding treatment is performed on a base material of a compressor vane made of high-speed tool steel (SKH51) and then an ion plating treatment is performed,
The following problems arise. 1. A bulge is likely to occur in the nitrided corner portion. 2. The impact resistance is slightly reduced to make it brittle, and chipping is likely to occur at corners. 3. Since two different kinds of processing, ie, nitriding and ion plating, are performed, the manufacturing cost increases.

The present invention has been made in order to solve these problems, and an object of the present invention is to provide a sliding surface having an ion plating layer in which Cr2 N-type chromium nitride and CrN-type chromium nitride are mixed. Provide compressor vanes with excellent abrasion, impact resistance, and peeling resistance, which are less likely to cause bulging at the corners or chipping at the corners, and which can reduce manufacturing costs. Is to do.

[0005]

In order to achieve the above object, the present invention employs a high speed tool steel (SKH5).
An ion plating layer containing a mixture of Cr2 N-type chromium nitride and CrN-type chromium nitride is provided directly or through an undercoat ion plating layer on at least the sliding surface of the base material of the compressor vane of 1). It has been formed.

As the undercoat, an ion plating layer of chromium metal or an ion plating layer in which chromium metal and Cr 2 N-type chromium nitride are mixed is formed. The thickness of the ion plating layer formed on the base material of the compressor vane is 4 to 11 μm at the tip end surface, 1 to 5 μm at the narrow narrow side surfaces, and 3 mm at the wide front and back surfaces.
It is preferable to set it to 7 μm.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A compressor vane according to the present invention will be described based on a first embodiment shown in FIGS. FIG. 1 is a perspective view of a first embodiment. In a compressor vane 1, a curved end surface 5 at the tip slides on an inner peripheral surface of a compressor housing or an outer peripheral surface of a rotor. Sliding on the inner surface of the vane groove, narrow side surfaces 7 slide on the side surfaces of the compressor housing.

FIG. 2 is a cross-sectional view of the first embodiment.
The base material 2 of quenched and tempered high-speed tool steel (S
KH51). On the sliding surface of the base material 2, an ion plating layer 3 in which Cr2 N-type chromium nitride and CrN-type chromium nitride are mixed is formed. The thickness of the ion plating layer 3 is such that the tip surface 5 has a maximum of 4 to 11 μm,
The front and back surfaces 6 are 3 to 7 μm slightly thinner. Although not shown, the thickness of the ion plating layers on both sides is a minimum of 1 to 5 μm.

The ion plating layer 3 is formed by setting the vane and a container of an ion plating apparatus (not shown). First, a cleaning process using ion bombardment is performed. The substrate temperature in the ion plating method is usually controlled to about 200 to 600 ° C. Preferably, it is controlled to 550 ° C. or lower. Next, nitrogen gas is introduced as a reaction gas into the container, Cr is evaporated into the reaction gas, ionized in a gaseous state, the base material is negatively biased, and the reaction gas and the vaporized substance ions are formed on the surface thereof. To form an ion plating layer in which Cr2 N-type chromium nitride and CrN-type chromium nitride are mixed. Finally, a paper wrap is applied to the surface on which the ion plating layer is formed to finish to a desired surface roughness. The paper wrap may be applied before the ion plating treatment to remove an oxide film on the surface of the base material.

The vane 1 has an ion plating layer 3 having a hardness of Hv 1800 or more in hardness of the coating itself on the sliding portion.
Since it is covered with, it has excellent wear resistance and good compatibility with the mating material in terms of wear. Although the hardness of the base material is about Hv750 and the hardness difference from the ion plating layer is large, the ion plating layer adheres and is excellent in peeling resistance due to ion bombardment performed as a pretreatment for ion plating. . Also, unlike the conventional nitride layer, the corner portion does not rise or chip when the ion plating layer is formed.

Further, since the vane is only subjected to the ion plating treatment on the base material, the production cost is greatly reduced as compared with the conventional vane which has been subjected to the nitriding treatment and the ion plating treatment. In addition, Cr2 N-type chromium nitride and CrN-type chromium nitride are mixed by adjusting the nitrogen gas pressure.

By forming such a mixed composition film, C
It is superior in abrasion resistance to the chromium nitride film of r2 N type alone. The content ratio of CrN-type chromium nitride to Cr2 N-type chromium nitride is desirably 45% or more, preferably 80% or more, of the total CrN-type chromium nitride. In this case, the strength of the ion plating layer can be improved without lowering the wear resistance. If further wear resistance is required, the wear resistance can be improved by using CrN type chromium nitride alone.

[0013]

Next, an embodiment shown in FIG. 3 will be described.
As shown in FIG. 3, the vane 1a of the second embodiment is
Then, as an undercoat, an ion plating layer made of chromium metal or an ion plating layer 4 in which chromium metal and Cr2 N-type chromium nitride are mixed is formed, and Cr2 N-type chromium nitride and CrN-type chromium nitride are formed thereon. This is one in which a mixed ion plating layer is formed. This undercoat ion plating layer 4
And the next ion plating layer 3 can be formed continuously by adjusting the reaction gas pressure in the same ion plating apparatus container. Therefore, these processes are regarded as one ion plating process. be able to. The hardness of the inner ion-plating layer 4 of the undercoat is higher than the hardness of the base material 2 and lower than the hardness of the outer ion-plating layer. And the inconvenience due to the hardness difference is reduced.

The other configurations and effects of the second embodiment are the same as those of the first embodiment. In the present invention, the ion plating layer 3 may be formed only on the tip surface 5.

[0015]

As described above, in the compressor vane of the present invention, the base material is made of high-speed tool steel (SKH51), and the sliding surface thereof has a Cr2 layer without an intermediate nitride layer.
Since an ion-plating layer in which N-type chromium nitride and CrN-type chromium nitride are mixed is formed, wear resistance, peeling resistance, and abrasion with a mating material are improved in the same manner as a conventional intermediate layer with a nitride layer formed. However, unlike the conventional one, there is no possibility that the corner portion is raised or chipped, and since there is only one in the processing step, an excellent effect of reducing the manufacturing cost is achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a first embodiment of a compressor vane according to the present invention;

FIG. 2 is a sectional view of the first embodiment,

FIG. 3 is a sectional view of a second embodiment,

[Explanation of symbols]

 1, 1a: Vane 2: Base material 3: Ion plating layer 4: Ion plating layer (undercoat) 5: Tip surface 6: Front and back surface 7: Side surface

Claims (3)

[Claims] 1. A Cr2 N-type chromium nitride and a CrN-type chromium nitride are provided directly on at least a sliding surface of a base material made of high-speed tool steel (SKH51) or through an undercoat ion plating layer. A vane for a compressor, wherein a mixed ion plating layer is formed. 2. The compressor vane according to claim 1, wherein the undercoat is an ion plating layer formed of chromium metal or a mixture of chromium metal and Cr2 N-type chromium nitride. 3. The thickness of the ion plating layer is 4 to 11 μm on the tip end surface of the vane, and 3 to 3 on the wide front and back surfaces.
The vane for a compressor according to claim 1 or 2, wherein both sides of the narrow width are 7 m and 1 to 5 m.