JPS63111313A - Sliding device - Google Patents

Abstract

PURPOSE:To obtain superior sliding characteristic by coating a sliding surface made of ceramic with a hard thin film for increasing the abrasion resistance of the sliding surface. CONSTITUTION:In the shaft 1 of a sliding device which comprises the shaft 1 and a bearing 2, the sliding surface of a base body 1a formed with ceramic is coated with a hard thin film 1b. Further, the bearing 2 is formed with ceramic. Since the sliding surface of the shaft 1 is coated with the hard thin film 1b, the abrasion resistance of the sliding surface is large, and the particle structure of the sliding surface is in a state of roundish configuration. Accordingly, little quantity of abrasion may occur in the bearing 2, and then superior sliding characteristic can be maintained for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sliding device that constitutes a rotating and linear sliding portion of a bearing, a seal portion, etc. of a mechanical device.

[Conventional technology]

Sliding devices that constitute the sliding parts of mechanical devices are required to have low frictional resistance and high wear resistance. For example, to reduce abrasion resistance, shafts made of steel with molybdenum added, and bearings made of resin made of tetrafluoroethylene, etc., were used. In addition, to increase wear resistance,
Shafts made of heat-treated or nitrided steel, or made of carbide were used.

[Problems with conventional technology]

However, shafts made of molybdenum-added steel and bearings made of resin have low wear resistance and have a short lifespan, and sliding devices using these have the problem of requiring a lot of money and time to replace parts and maintain them. In addition, the surface layer of shafts made of surface-treated metal tends to peel off easily, and shafts made of sintered carbide grains tend to have particles falling off during long-term use. was there.

In other words, a sliding device with low friction resistance, high wear resistance, and excellent long-term sliding properties has not been developed.0 [Means for solving the problem] In view of the above, In the present invention, one member that slides on each other is made of metal or ceramic, and the other member is made of ceramic, and a hard thin film is coated on the sliding surface to constitute a sliding device.

〔Example〕

The present invention will be explained in detail below.

Fig. 1 shows a sliding device consisting of a shaft l and a bearing 2, in which the shaft l has a hard thin film 1b coated on the sliding surface of a base body 1a made of ceramic, and the bearing 2 is made of ceramic. It is what was done.

By coating the hard thin film 1b on the sliding surface of the shaft 1, the wear resistance of the sliding surface is high, and the grain structure of the sliding surface is rounded, so that the bearing 2 is not worn out. The amount of sliding is small, and good sliding characteristics can be maintained over a long period of time. Further, since the base 1a and the bearing 2 of the shaft 1 are made of ceramic, there is no risk of deformation.

In fact, the substrate 1a of axis l was formed of alumina ceramic and a hard thin film tb''Il:TiN, respectively, and the surface conditions were observed.The surface particle structure of the substrate la made of alumina ceramics is shown in Figure 3. As shown in Fig. 4, the particle structure of the surface after the hard thin film 1b made of TiN is applied, the surface of the substrate 1a has an uneven shape with many sharp parts, whereas the hard thin film 1b formed on the surface has an uneven shape. The rear surface is rounded while maintaining its uneven shape.If a sliding device is constructed using this shaft l, the contact area of the sliding part will be reduced due to the unevenness of the sliding surface. Since the particle structure is rounded, the hard thin film 1b is difficult to peel off, and the bearing 2
There will be no damage to the side sliding surfaces.

Further, in the above embodiment, the bearing 2 is made of ceramic, but it may be made of metal, and the bearing 2 may be made of metal. 2 may be both made of lamic and both sliding surfaces may be coated with a hard thin film.

Next, a wear resistance test was conducted using the apparatus shown in FIG.

A test member T with a diameter of 40M and a thickness tOW was prototyped using various combinations of base materials and thin film types shown in Table 1, and was pressed against a mating member A of the same shape with a five-wheel load.
,000 revolutions per minute, and the time until rotational unevenness or eccentricity occurs due to wear, with TiN coated on the surface,
Four types of alumina coated with TiC were prepared, and the thin films were formed to a thickness of m- by the CVD method.

Table 1 ◎・・・・・Rotation unevenness and eccentricity occur after a, ooo time Φ・・・・・・・・2,000 1 #
O・・−・−・・1,500 # O・・−・−・・1,000 # #Δ・
・－・・・・・・ 500 ＃＃×・・・－
... 100 # # In Table 1, when stainless steel or carbon steel is used as the test member T, when the mating member A is stainless steel or alumina, the effects of wear begin to appear after about 100 hours. On the other hand, as the mating member A, TiN or Ti is used on alumina.
When one coated with C was used, it had a long life of about 500 hours. Conversely, if we look at the case where stainless steel is used as the mating member A, when the test member T is stainless steel or carbon steel, it takes about 100 hours, but when the test member T is made of ceramics KTiC, TiC,
When using a material coated with the same material, the lifespan was longer by more than 500 hours. In other words, it can be seen that if one of the two sliding members is made of ceramic coated with a hard thin film, the life will be extended. In particular, if a hard thin film is formed on both the test member T and the mating member A, 2. It is very good when using a material. (1
It had a long lifespan of over 00 hours. However, when both members were coated with the same substance, the lifespan was short. Generally, when materials with the same hardness are slid against each other, there is a large amount of wear on each other, so the hard thin films deposited on both members may be made of materials with different hardnesses, such as TiN and TiC, for example.

In addition, in Table 1, as the test member T, TiC on alumina
The rotation time and the test member T were calculated using three types: alumina coated with TiN, alumina coated with TiN, and stainless steel treated with tuftlite. The relationship between the amount of wear and tear was investigated. The results are shown in FIG. 5, and it can be seen that the test member T, in which Tic and TiN were coated on alumina, had a smaller amount of wear.

Furthermore, for various combinations of substrates and thin films shown in Table 1, test members T were produced by varying the thickness of each thin film, and using a mating member A made of stainless steel,
After conducting the same wear resistance test as above for 100 hours, the surface condition was observed and the results are shown in Table 2.

Table 2 O: No abnormalities Δ: Part of the thin film peels off: Due to wear, the base is slightly exposed, as shown in Table 2. If the thickness of the hard thin film is less than 0.1μm, the underlying layer will be exposed, and if the thickness is more than 5μm, it will not only peel off easily, but also require
It took over 4 hours and was inefficient. That is, a hard thin film having a thickness of 0.1 to 5 μm was excellent.

In addition, the surface of the surface on which the hard thin film is formed has a smooth uneven shape as described above, but as a result of various experiments,
The surface roughness of 0B-15R was excellent.

In the above embodiments, only the CVD method was shown as a method for forming a hard thin film, but depending on the material of the substrate and the type of thin film, PVD methods such as ion blasting method, sputtering method, ion beam deposition method, etc. may also be used.

〔Effect of the invention〕

As described above, according to the present invention, one member that slides on each other is made of metal or ceramic, and the other member is made of ceramic, and a hard thin film is coated on the sliding surface. By configuring the device, the sliding surface not only has high wear resistance and a long service life, but also reduces frictional resistance because the particle structure of the surface is rounded while maintaining appropriate unevenness. It is possible to provide an excellent sliding device that does not damage the mating member.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a sliding device R according to an embodiment of the present invention. FIG. 2 is a perspective view showing an apparatus for testing the wear resistance of a sliding device. Figure 8 is an electron micrograph showing the particle structure of the surface of the alumina ceramic shaft of the sliding device shown in Figure 1, and Figure 4 is a hard thin film made of TiN on the base shown in Figure 3. 2 is an electron micrograph showing the particle structure of the surface after coating. FIG. 5 is a graph showing the relationship between rotation time and amount of wear. 1, ......Axis 2, ......Base

Claims (1)

[Claims] A sliding device characterized in that one member that slides on each other is made of metal or ceramic, and the other member is made of ceramic and a hard thin film is coated on the sliding surface.