Microstructural Modeling and Dynamic Process Simulation of Laser-Assisted Machining of Silicon Nitride Ceramics With Distinct Element Method

摘要: The distinct element method (or discrete method, DEM) is applied to simulate the dynamic process of laser-assisted machining (LAM) silicon nitride ceramics. This motivated by fact that LAM ceramics shows a few complicated characteristics such as spontaneous crack formation, discontinuous chips, etc. Thus, using two-dimensional code, PFC2D , microstructure β-type ceramic modeled, and resulting temperature-dependent synthetic specimens are created first, then, simulations conducted. DEM model validated through comparing predicted results with those from experiments under different cutting temperatures in terms force, chip size, depth subsurface damage. Furthermore, mechanisms analyzed aspects material removal, segments, surface/subsurface damage, well initiation, propagation, coalescence.