Discrete Element Method Simulation and Experimental Study of Silicon Carbide on Pre-Stressed Machining

In this paper, the technology of pre-stressed suitable for ceramic materials machining was presented. And the discrete element method (DEM) model of SiC ceramic was established which could describe the mechanics behaviour of inter-granular and trans-granular fracture. The crack's initiation and propagation in cutting processes with different pre-stressed were simulated, and the scratching tests were carried out to confirm the validity of simulation. Both the DEM simulation and the experimental study showed that in certain pre-stressed conditions, with the increasing of pre-stressed, the number of radial cracks reduced and the transverse cracks replaced the radial cracks to some extent, and also caused the material removal in the form of smaller fragments. Using pre-stressed machining can decrease the machining damage and improve the surface quality; and further prove that using DEM to simulate the pre-stressed machining of SiC was feasible.