Friction and Wear Characteristics of Silicon Carbide Composite Doped With Nickel in Dry Sliding

The friction and wear behaviors of reaction sintered Si/SiC and its composites doped with Ni(Si/SiC Ni) in dry sliding were investigated in a temperature range of 15~600 ℃ on a pin on disc tribometer. It has been found that Si/SiC Ni composite made from SiC of smaller grit size has good self lubricity and wear resistance at high temperature as compared with Si/SiC at the same conditions. The inclusion of Ni has margin effect on the friction behavior of Si/SiC composite made from SiC of larger grit size but decreases its wear rate greatly. XRD analysis of the wear debris and SEM observation of the worn composite surfaces indicate that the oxides such as NiO, Ni 2O 3, and SiO 2 generated during the friction process at 600 ℃ account for the good self lubricity of SiC Ni composite at high temperature, whicle SiC primarily acts to carry load and increase the wear resistance of the composite.