Traditional lubrication by oil sometimes does not work because of the high temperature, fast speed and excessive load of the aeroengine bearings. The Graphite-like Carbon coating is used to improve the insufficient lubrication in this paper. And the micro hardness, the friction coefficient and the wear rate tests are offered: with GLC, the hardness is increased twice at least, its friction coefficient is 25% and the wear rate is 1/100 when contrasted with that of the typical bearing's material. The tests and calculation results show:the wear cycles of the GLC coated W9Cr4V is more than 400 times of that of the uncoated W9Cr4V and even when the GLC coating is worn out, the friction coefficient of W9Cr4V is only 0.15 which can effectively lubricate for the bearing for a short period of time when the liquid lubrication does not work. So it is proved to be effective in improving the wear resistance and reliability of bearings. In this paper,the important conclusions are given below:(1)the hardness of the material’s surface is increased twice at least with GLC coating.(2)the coefficient of the GLC is l/4 of that of W9Cr4V.And the coefficient remains stably below 0.15 while tests is going on. The wear rate of the GLC is l/5 of W9Cr4v. With GLC the W9Cr4V can keeping self-lubricated for a long time when the liquid lubrication does’t work.(3)the tests and the calculated results show:the friction coefficient increased to 0.5 and the friction moment is as much as 22%of the turning moment of the shaft when the wearing cycles are 700.And a 2(pm)thick coating will be worn through after 280000 wearing cycles which is 400 times of those when the bearing is not GLC coated.If the friction coeffcient can be kept low even after the coating is worn out.the number of wearing cycles will reach 840000 and the wear lifc can be prolonged by 1200 times compared with that of the uncoated material.

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