The Study of Self-lubricating Sintered Nickel Matrix Material and its Applications

摘要

In the paper, a self-lubricating sintering nickel matrix material has been developed and inserted into ball bearing as new solid lubricant at 600°C. For obtaining good lubricating property, some additives are added into the nickel matrix and sintered at elevated temperature. Research shown that CaF_2 has great contribution to lubrication, but amount of CaF_2 must be controlled, and that the lubricating behaviors can be further improved by adding a mixture of CaF_2 and BaF_2, but the proportion of CaF_2 / BaF_2 should be also controlled so that a eutectic compound of Ni and CaF_2 / BaF_2 can form during the sintering. In the paper, the high temperature self-lubricating mechanism of the material has been investigated. Topography and compositions of surface film are analyzed by using SEM and X-ray. Based on good self-lubricating behaviors of the sintering nickel matrix material, an oscillating ball face bearing has be manufactured. Its service test result show that the bearing has a service life over 1.2 x 10~5 cycle numbers and lower friction coefficient μ=0.26 - 0.12 from room temperature to 600°C at different loads.