JPH0361386A - Sliding member - 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 lubricant-free bearing material that slides on a shaft, and particularly to a sliding member suitable for a bushing of a serpentine autotensioner.

[Prior Art] Conventionally, as an example of a lubricant-free bearing material, a metal substrate, a sintered layer formed integrally on the surface of the metal substrate and sintered with copper-based metal particles such as phosphor bronze or hull particles, Various fillers (lead, zinc, molybdenum sulfide,
ISS is a shock absorber whose member is integrally formed with a fluororesin layer containing graphite, alumina, and silica.
There is a disclosure that white surface can be applied (Japanese Patent Application Laid-Open No. 61-2484
Publication No. 6).

[Problems to be Solved by the Invention] However, when the above-mentioned non-lubricated bearing material is used as the moving surface of the bushing and the shaft is used as a mating member to slide, the wear resistance of the non-lubricated bearing material is not sufficient, so it cannot be used under high loads. In circumferential motion, problems may occur in which the copper particles in the sintered layer are crushed or the iron in the metal substrate is exposed due to excessive wear and seizes or adheres to the shaft of the mating member.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the wear resistance of a non-lubricated bearing material to provide a sliding member with increased durability.

[Means for Solving the Problems] The opening member of the present invention includes a metal substrate and a sintered layer integrally formed on the surface of the metal substrate and having wear-resistant particles mainly made of copper-based metal sintered therein. and a fluororesin layer impregnated and coated on the sintered layer, and the 11i1 abrasive particles contain 2 to 10% by weight of silicate fibers.

The purpose of the surrounding member of the present invention is to improve the wear resistance of the sintered layer. Therefore, the sintered layer is composed of wear-resistant particles made of copper-based metal in which silicate-based fibers are specifically incorporated.

The silicate fiber is added in an amount of 2 to 10% by weight based on the copper metal. If the amount of crinkled yarn fibers contained in the copper-based metal is less than 2% by weight, no effect of the addition will be observed and the wear resistance of the sintered diagram will not improve. If the amount of silicate fiber exceeds 10% by weight, the strength of the wear-resistant particles decreases, and the wear resistance of the sintered layer decreases.
This is not preferable because the four fibers attack the mating member and increase the amount of friction on the mating member. The crinkle cate fibers have a melting point higher than that of the copper metal, maintain the fiber shape within the wear-resistant particles, and reinforce the wear resistance of the sintered layer.

Among them, alumina silicate fibers are preferred.

As the copper-based metal forming the sintered layer, phosphor bronze, lead bronze, etc. can be used.

Wear-resistant particles can be easily formed, for example, by mixing silicate fibers with molten copper metal and using a cast atomization method. The wear-resistant particles are then molded to a predetermined thickness on a metal substrate and sintered in a reducing atmosphere to form a sintered layer.

Note that as the metal substrate, an iron-based metal substrate is usually used as in the conventional case.

The formed sintered layer is coated with a fluorine-based resin to impregnate the pores in the sintered layer and coat the surface thereof to form a fluorine-based resin layer. This fluorine-based resin layer increases the lubricity of the sliding surface.

As the fluorine resin, PTF (polytetrafluoroethylene), PFA (tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer), ETFE (ethylene/tetrafluoroethylene copolymer), etc. can be used. Solid lubricants such as zinc, lead, molybdenum disulfide, graphite, alumina, and silica may be added to this resin as additives.

[Function] The 13 moving member of the present invention has a sintered layer composed of wear-resistant particles made of copper-based metal containing 2 to 10% silicate fiber, and whose surface is covered with a fluorine-based resin layer. ing. For this reason, the fluorine-based resin layer increases lubricity and improves the wear resistance of the sintered structure. The shape of the wear-resistant particles is maintained by the silica 1 fibers, making them difficult to crush. Therefore, even if this rotating member is used on a high-load IS moving surface, the inner metal base material will not be exposed due to wear and become stuck to the mating member, and its durability will be improved. Also, the tails of the silicate fibers are suitable so that they do not damage the mating material.

[Example] This will be explained in detail below using Examples.

FIG. 1 shows a sectional view of an autotensioner to which this 18-motion member is applied.

This auto tensioner is used to maintain a constant tension of the bell 1 which transmits the drive of the crank of the automobile to the auxiliary equipment. A bushing 3 is inserted into the outer periphery of a shaft 2 extending from a base 11, and a support portion 10 that rotatably supports the pulley 1 via the bushing 3 is attached. shaft 2
and the support part 10 are connected to each other via a spring 7 so that the support part 10 can swing. The belt is put around the pulley 1, and the tension of the belt is adjusted by swinging the support part 10 while the pulley 1 rotates. When adjusting the tension, the support part 10 performs a swinging movement around the shaft 2, so that the outer circumferential surface of the shafts 71 to 2 and the bush 3
This results in 18 reciprocating movements in the circumferential direction.

Figure 2 is a schematic cross-sectional view of the sliding surface formed on the inner circumferential surface of the pushbutton 3, in which a sintered layer 5 of copper-based metal particles with a thickness of about 300 μm is formed on a metal substrate 4 made of iron. , the pores of the sintered layer 5 are impregnated with PTFE resin 6, and the surface of the sintered layer is coated with about 20 μm.
A fluororesin layer with a thickness of m is formed.

(Example 1) Bushes having four types of sintered layers shown in Table 1 were prepared.

5% by weight of silicate fiber alumina silicate fiber (trade name Karaol) is mixed with molten phosphor bronze,
Abrasion-resistant particles with a diameter of 100 μm were prepared using the Gas 71-Meiss' method. Copper-based metal particles containing Marikibon fibers and potassium titanate fibers were produced in a similar manner. A molded layer of a predetermined thickness is formed on the surface of the metal substrate from these wear-resistant particles,
It was sintered at about 1000°C to form a sintered layer with a thickness of 300 μm. Approximately 150% of P T F E is applied to the surface of this sintered layer.
It was coated to a thickness of μm and heated to infiltrate the resin into the internal pores to form a resin layer integrally on the surface to form a sliding surface. This member having a sliding surface was processed into a bush with dimensions of 20 mm x 40 mm. As a comparison, a bushing was prepared in which a sintered layer and a resin layer were formed using phosphor bronze particles containing no alumina silicate and copper-based metal particles containing carbon fibers or potassium titanate fibers that were previously installed.

(Evaluation) After conducting a durability test (E/G rotation speed 500 Orpm, 500 hours) using 845C as the mating shaft of the produced bushing and the above-mentioned auto tensioner, the amount of wear on the bushing and the mating shaft was measured. .

The results are shown in Table 1.

As shown in Table 1, the amount of wear is shown in Table 1.The phosphor bronze of No. 1 has a sintered layer made of wear-resistant particles containing 5% by weight of alumina silicate fibers, and the phosphor bronze of No. 1 that does not contain alumina silicate fibers. Compared to the sintered layer of particles, the wear of the bushing was the smallest and was better. Carbon fiber (NO03) and potassium titanate fiber (NO03) are used as reinforcing fibers.
No. 94) was used, and the bushing was not significantly different from No. 2, a wear machine with a sintered layer of phosphor bronze particles. In addition, the amount of wear on the shaft increases slightly by filling the bush with silicate fibers, but this is not a problem compared to other comparative examples (No. 92 to 4) (Example 2) In Example 1, A sintered layer was formed using wear-resistant particles formed by changing the blending amount of alumina silicate fiber to Phosphorus Blue 111 from 1 to 20% by weight, and each bushing was produced.Example 1 Figure 3 shows the results of a circumferential motion test conducted in the same manner as above.

The wear amount of the bushing is 1 for alumina silicone to 1 star for fiber.
In the case of weight%, it is larger at 160μm compared to 100μm or less in the case of type 2 beam%.Also, if the alumina silicate fiber star exceeds 101ffi%, the strength of the sintered layer decreases, resulting in poor wear resistance. Reduced wear amount to 150tim
(In the case of alumina silicate fiber @ 15%). Regarding wear and tear on the shaft, when the alumina silicate fiber exceeds 10 layers, its aggressiveness increases and the amount of wear on the shaft increases rapidly. Therefore, the optimum loading of alumina silicate fibers contained in the wear-resistant particles is between 2 and 10 percent.

[Effects] In the sliding member of the present invention, the wear-resistant particles of the sintered layer are filled with silicate fibers in a range of 2 to 0%, so the wear resistance and durability of the sliding member are improved. It has hardness and strength that balances i4 abrasion resistance and opponent attack resistance. Therefore, it can be used for bushings that are high-load surrounding members.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the auto-tensioner, Figure 2 is a schematic cross-sectional view of the sliding surface of the bushing, and Figure 3 is a measurement of the amount of wear when changing the content of wrinkled fibers. This is a line graph that does not show the results.

Claims (1)

[Claims] A metal substrate, a sintered layer integrally formed on the surface of the metal substrate and sintered with wear-resistant particles mainly made of copper-based metal, and a fluorine-based resin layer impregnated and coated on the sintered layer. A sliding member characterized in that the wear-resistant particles contain 2 to 10% by weight of silicate fibers.