JPS61281087A - Sliding material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a sliding material made of a ceramic composite having excellent sliding properties and wear resistance. This invention relates to a sliding material made of a ceramic composite that is extremely suitable for.

[Conventional technology]

In general, ceramics have excellent physical and chemical properties and are excellent materials for wear-resistant materials such as mechanical seals and bearings, and corrosion-resistant materials that handle highly corrosive solutions such as acids and alkalis.

By the way, many ceramics that have high hardness and excellent wear resistance generally have poor self-lubricating properties. Therefore, as a material for solving the above-mentioned problems, the
Publication No. 9-282981 states, ``Ceramics is made of a ceramic base material with fine cavities scattered in the surface layer, and the cavities are filled with a solid lubricant with excellent shearing dynamic characteristics and fixed. The existence form of the solid lubricant in the ceramic sliding material is determined by the size and depth of the cavities that exist in the ceramic as shown in Table 1, and it is relatively difficult to fill and is easily desorbed during sliding. In addition, the solid lubricants are present only on the surface layer of ceramics and are unsuitable for applications such as mechanical seals and sliding bearings that require long-term durability.

[Means for solving problems]

As a result of extensive research aimed at solving the above-mentioned problems, the inventors of the present invention discovered that a ceramic sintered body having grooves formed on the sliding surface is provided with a lubricating substance filled in the grooves. The present invention was completed based on the new finding that a sliding material made of a ceramic composite has sliding characteristics and wear resistance that are extremely suitable for applications such as mechanical seals and bearings.

The present invention will be explained in detail below.

The sliding material of the present invention is required to be a ceramic composite body formed by filling a lubricating substance into the grooves of a ceramic sintered body having grooves formed on the sliding surface. The reason for this is that the lubricating substances filled in the grooves are generally soft and have poor thermal conductivity, so when only lubricating substances are used as sliding materials, there are significant restrictions on the conditions of use. Although it is difficult to apply it to applications such as mechanical seals and bearings, it is possible to create a desired shape even with a salvage material by filling it into the grooves provided in the ceramic sintered body as described above. can hold,
Moreover, the heat generated at the sliding surface can be efficiently dissipated.

In order to retain the soft lubricating substance and improve heat dissipation, it is desirable that the Cera T2 sintered body has high rigidity and high thermal conductivity, such as silicon carbide sintered body. It is preferable that the material is at least one selected from aluminum sinter, AJL/E sintered material, and aluminum nitride sintered material.

The 8 lubricating substances are desirably ones that can be easily filled into the grooves and have excellent self-lubricating properties. group polyether resin, polysal7one resin, polyether sulfone resin, polyether ether ketone resin, polyarylate resin, polyester resin, fluororesin, polyamideimide resin,
Polyimide resin, epoxy resin, polyethylene resin, polypropylene resin, silicone resin, styrene resin I)
At least one selected from Q nitrile tree IJi and urethane tree 711 is preferred.

The sliding material has a lubricating substance and Cera Zy on the sliding surface.
It has the advantage that the area ratio of the sintered body and the filling depth of the lubricating substance can be arbitrarily and easily set according to the purpose of use.

The grooves provided in the ceramic sintered body can have various shapes depending on the intended use of the sliding material.

For example, when the sliding material is a mechanical seal, it can be formed into a concentric circular shape as shown in FIG. 1, a radial shape as shown in FIG. 2, a thinly wound shape, or a combination thereof; When the sliding material is a sliding bearing, it can be formed perpendicular to the axial direction as shown in FIG. 8, parallel to the axial direction as shown in FIG. 4, spirally, or a combination thereof. In addition to the relatively simple shape described above, the groove may be formed by a curved line with a small curvature and/or a plurality of continuous straight lines, if necessary.

Next, a method for manufacturing the sliding material of the present invention will be explained.

The sliding material made of the ceramic composite of the present invention is produced by molding the starting material ceramic powder into a formed body of any shape and sintering it to form a ceramic sintered body with grooves on the sliding surface. and then filling the groove with a lubricating substance.

As a method for sintering the ceramic powder after forming it into a formed body of an arbitrary shape, it is advantageous to apply a conventionally known method of self-bonding by pressureless sintering or pressure sintering.

Examples of methods for providing grooves on the sliding surface of the ceramic sintered body include a method of molding using a mold designed to form grooves, a method of machining the formed body before sintering, or a method of machining the formed body before sintering. A method in which the shape is sintered and then machined can be applied.

As a method of filling the groove with the lubricant substance, for example, a method of heating and melting a resin to fill the groove, or a method of pasting a lubricant substance that has been previously formed to match the shape of the groove can be applied. .

Note that the sliding material made of the ceramic composite filled with the lubricant substance may be finished by, for example, lapping to make the surface more precise and smooth after being filled with the lubricant substance. can.

Next, the present invention will be explained by examples.

Example 1 100 parts of stretchable alumina powder with an average particle size of 0.4 μm and a purity of 98% by weight, 2 parts by weight of polyvinyl alcohol, 1 part by weight of polyethylene glycol
, 0.5 parts stearic acid and 100 ffiff of water.
Part i was mixed and then spray dried.

Collect an appropriate amount of this dried material and use a metal mold to
After molding at a pressure of t71, it is machined to an outer diameter of 35M.
A ring-shaped formed body with an inner diameter of 25 fl, a thickness of 511 II, and two grooves each having a width of 2 m and a depth of 1.5 ff as shown in FIG. 1 was obtained.

Next, the formed body was placed in an alumina crucible, heated to a temperature of 1600'C in a humidified hydrogen stream, and held for 1 hour to obtain a sintered body.

Furthermore, polytetrafluoroethylene was sintered into the grooves of the sintered body. Then, the surface was polished and 5001Sll
When an end face load of 10#f/d was applied at a sliding speed of C, the friction coefficient was 0.08 to 0.16, and the abrasion coefficient was 8 d), and was found to have extremely excellent sliding properties.

Implementation side 2 Average particle size is 0.28 μm, β type crystal content is 94.6
For 100 parts by weight of silicon carbide powder with a purity of about 98.5% by weight, 1 part by weight of boron carbide powder, 2 parts by weight of carbon black powder, 5 parts by weight of polyvinyl alcohol,
300 parts by weight of water was added, mixed in a ball mill for 5 hours, and then spray-dried.

Collect an appropriate amount of this dried material and use a metal pressing mold to
After pre-forming at a pressure of t/d, it was hydrostatically pressed at a pressure of 8t/cd to give a diameter of 'l Q wpx and a length of 101
No. 111 cylindrical product shapes were obtained. Next, the formed body was processed into the shape of a plain bearing as shown in FIG.
It was heated to a temperature of 00''C and held for 0.2 hours for sintering.

The density of the obtained sintered body was 8.16 fM.

Next, polytetrafluoroethylene was filled into the grooves on the inner surface of the sintered body in the same manner as in Example 1, and the inner surface was polished to produce a sliding bearing with an inner diameter of 10λl.

This bearing is highly lubricated! It had extremely good sliding characteristics even in the case of lint, and was also extremely durable.

〔Effect of the invention〕

As mentioned above, the sliding material made of the ceramic composite of the present invention has extremely excellent sliding properties and wear resistance, and is an extremely suitable material for mechanical components such as mechanical seals and bell bearings. It is extremely useful industrially because it can significantly improve the durability and reliability of.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing a partially cut away mechanical seal in which grooves are arranged in a circular pattern created in Example 1, and Fig. 2 is a mechanical seal in which grooves are arranged in a radial pattern. Fig. 3 is a cross-sectional view of the sliding bearing prepared in Example 2 in which the grooves were provided perpendicular to the axial direction, and Fig. 4 is a cross-sectional view of the slide bearing in which the grooves were provided in parallel to the axial direction. FIG. 3 is a cross-sectional view of a sliding bearing.

Claims (1)

[Scope of Claims] 1. A sliding material made of a ceramic composite comprising a ceramic sintered body having grooves formed on its sliding surface and a lubricating substance filled in the grooves. 2. The sliding material according to claim 1, wherein the ceramic sintered body is at least one selected from silicon carbide sintered bodies, alumina sintered bodies, and aluminum nitride sintered bodies. . 3. The lubricating substance is polyamide resin, polyacetal resin, polycarbonate resin, polybutylene terephthalate resin, polyphenylene sulfide resin, aromatic polyether resin, polysulfone resin, polyether sulfone resin, polyether ether ketone resin, polyarylate resin. , polyester resin, fluororesin, polyamideimide resin, polyimide resin, epoxy resin,
The sliding material according to claim 1 or 2, which is at least one selected from polyethylene resin, polypropylene resin, silicone resin, styrene acrylonitrile resin, and polyurethane resin. 4. The sliding material according to any one of claims 1 to 3, wherein the sliding material is a mechanical seal or a sliding bearing.