PTFE based composite sliding material

摘要

Bearing 4 is fabricated by providing porous sintered metal layer 7 of copper alloy on the surface side of back metal layer 5 of steel plate through copper plating layer 6 and coating the inside and the surface of porous sintered metal layer 7 with sliding material 8 by impregnation. Sliding material 8 comprises 1-25 vol.% of tetrafluoroethylene-perfluoroalkylvinyl ether copolymer resin, 1-25 vol.% of at least one member selected from the group consisting of oxybenzoylpolyester resin and polyimide resin and 0.1-10 vol.% of hard particles having a Mohs hardness of 4 or more and average particle sizes of 5 žm or less such as Al2O3 and Sic, the balance being polytetrafluoroethylene resin (55 vol.% or more of the total siding material) as the main component. 0.5-25 vol.% of a solid lubricant such as graphite and MoS2 can be further contained in total together with the hard particles. The sliding material containing polytetrafluoroethylene resin as the main component has an improved fretting wear resistance particularly when used as a bearing material, and may be used in a throttle valve.