Solid particle erosion-wear behaviour of SiC particle-reinforced Si matrix composite and neat Si-A comparison

Reaction-bonded SiC/Si (viz. RB-SiC/Si, also known as SiC particle-reinforced Si matrix composite) possesses high brittleness and hardness, which benefit its engineering applications such as mechanical seals and waterlubricated bearings, but limit its micro-machining strategies simultaneously. In this paper, a purely mechanical method, solid particle erosion (or air-driving slurry jet impact, also called multiphase jet machining), was attempted to create micro-textures on this composite. The material removal behaviour was presented in detail and compared with the behaviour of neat Si. First, the related mechanisms were discussed; i.e., Si showed similar erosion appearances when subjected to the action of hard abrasives, while RB-SiC/Si showed completely different apperances. The dependence of erosion on impact angle for Si showed a typically brittle response while that for RB-SiC/Si showed a semi-brittle response when using small particles, but displayed a typically brittle response when using large particles. Particular attention should be paid to the synergistic effect between the material microstructure and employed particle size, which has an inherent correlation to the shift in maximum erosion from 90 degrees to 75 degrees /80 degrees. Achieved erosion information may provide reference for the jet machining of composite materials and the design of functional materials with erosion-resistant structure in the future.