Simulation investigation on crack initiation and propagation in ultrasonic assisted grinding of ceramics material

Based on smoothed particle hydrodynamics (SPH) method, the initiation and propagation of the cracks in the process of single abrasive impacting a workpiece are simulated during ultrasonic assisted grinding of ceramics material, and the removal characteristics and surface layer damage of material under different ultrasonic impact speeds are revealed. The simulation results show that the lateral and radial cracks occur initially when single abrasive is pressed into the workpiece at a certain depth under different impact speeds. With the increase in impact speed, the fractures in action area are significantly reduced, and the critical pressed depth of abrasive is decreased when a lateral crack is generated, while the critical pressed depth of abrasive is unchanged obviously when a radial crack is generated. By observing the propagation of the two kinds of crack with the increase in the pressed depth, it can be found that the propagation velocity and geometric size of lateral crack decrease, while the radial crack has no obvious change. The results show that the ductile region removal of ceramics material is enhanced with the increase in impact speed, while the damage of surface layer is not enlarged, and the surface quality is improved.