Discrete Element Method (DEM) Simulation and Investigation of SiC on Pre-stressed Machining

The discrete element model (DEM) of SiC ceramic material for pre-stressed machining was established by using a cluster method. The processes of crack propagation on different pre-stressed machining conditions were investigated by means of DEM simulation and scratching test. Damages and cracks of surface/subsurface were also observed. Both DEM simulations and experimental results showed that, while the magnitude of pre-stress was controlled in a certain range, the number of radial cracks reduced as the increasing of pre-stress magnitude; and there was a trend that the radial cracks were replaced by the transverse cracks, so as to the SiC materials were removed in the form of smaller fragments. It could be seen that machining damage was decreased and surface quality was improved by applying the pre-stressed machining method, and it was further proved that discrete element method was feasible to simulate the machining process of brittle materials.