Tribological characteristics of Cr3C2 ceramic with addition of TiC in high temperature and high pressure water

The effects of temperature and sliding speed on the tribological behavior of Cr3C2 with addition of TiC sliding on itself in deoxygenated water were investigated from room temperature to 300degC under the corresponding saturated vapor pressures. The friction coefficient increased at elevated temperatures at all sliding speeds, but decreased with increasing sliding speed. The specific wear rate of the disk was larger than that of the plate, and the dependence of the specific wear rate of the disk on sliding speed was different from that of the plate. The friction and wear properties of the material are considered to be controlled by tribochemical reactions to produce H2, C, CH4, C2H6 and CO2 and by microfracture. The relative molar ratios (H2/CH4, C2H6/CH4) where H2, CH4 and C2H6 were produced by the sliding friction were constant for all the wear tests. The relative molar ratio (H2/CH4) for the wear test at 300degC was smaller than that at the static corrosion of the specimens under the same hydrothermal condition as the wear test. (author)