Abstract: In order to avoid mesh constraint when simulating chip separation by finite element method, cutting process of single CBN abrasive grain is simulated by using coupling method of finite element method and smoothed particle hydrodynamics. Chip mechanism of single CBN abrasive grain and its geometric features’ effects on cutting deformation of workpiece material are analyzed according to the stress variation of CBN abrasive grain and workpiece material, and motion situation of smoothed particles in cutting layer. CBN abrasive grains’ scratching experiment is carried out by using abrasive block of vitrified bonded CBN wheel. It is concluded that workpiece material occurs plastic deformation, flows to the side and front owing to the extrusion of abrasive grain, and finally forms chip in front of abrasive grain. The shear angle increases with the increase of grain rake angle, it results in the decrease of ploughing and increase of cutting. The wear of the edges of abrasive grain is faster due to its lower strergth and larger contact stress. Wear abrasion and micro-breaking result in the dullness of abrasive grain.

Key words: machinofature technique and equipment, grinding, single abrasive grain, simulation, finite element method, smoothed particle hydrodynamics