Distinct Element Simulation of Laser Assisted Machining of Silicon Nitride Ceramics: Surface/Subsurface Cracks and Damage

Abstract

This paper applies distinct element method (DEM) to simulate the material removal process of laser assisted machining of silicon nitride ceramics and show the formation and propagation of surface/sub-surface cracks and damage. A synthetic specimen is created using particle clusters to approximate the granular microstructure of β-type silicon nitride ceramics. The effect of temperature on machining is considered by its influence on the material properties. In addition, some other parameters such as rake angle, depth of cut, local damping coefficient and cluster size are also considered in a parametric study. It shows that all these parameters influence surface/sub-surface cracks and chip formation of silicon nitride ceramics in laser assisted machining.