The dependence of friction coefficient vs. temperature and the effect of environment on the wear behavior of Ni- Cu- Re alloys have been measured. It was found that the friction and wear coefficient were reduced drastically at the elevated temperature. The results showed that Re played an important role in decreasing the friction and wear coefficient of alloys. The microstructure and composition about the oxide films and subsurface and the worn surface of alloys were investigated by means of metallography, X-ray diffraction, SEM and STEM methods. The low friction and wear coefficient related to the formation of volatile rhenium oxides during friction at high temperature. The rhenium oxides with low shear strength and melting point, form a soft glaze layer with CuO and NiO as the lubricant in the interface of tribosystem. The low melting point rhenium oxides improved the development of glaze layer. So alloys exhibited an excellent self-lubricing ability at high temperature. The results showed that the addition of Re and Cu in the Ni base alloys would imporved the friction and wear behavior at high temperature.
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