This paper aims to further understand the removal characteristics of hard and brittle crystal materials processed by diamond wire saws. The SPH and FEM coupling algorithm is used to analyze the dynamic response of material removal during the process of abrasive grain scratching a single crystal silicon carbide workpiece. The influence of abrasive particle contact force, workpiece surface morphology, and stress distribution under different abrasive grain depths and geometric shapes are studied. Two kinds of scratching methods:the constant depth scratching and the variable depth scratching of abrasive grains are analyzed on the dynamic response behavior of workpiece materials. The calculation results show that the components of the abrasive grain contact forces in all directions fluctuate with the scratching process. The x-axis direction and the z-axis direction of the abrasive particle contact forces have similar changes with time, and the fitted equations of the average abrasive particle contact forces during the smooth scratching period are respectively fx=3.0956h2.7264 and fz=11.3813h2.6214. The grain depth of abrasive particles is the main factor affecting the morphology and stress distribution of the workpiece during the scratching process. Compared with the conical abrasive grain, the cross-sectional morphology of the workpiece material scratched by spherical abrasive grain is rougher, but the deformation and damage layer depth of the workpiece material is smaller. The material response of the workpiece under variable depth scratching reflects the brittle-plastic transition of the workpiece as the depth of abrasive grain increases. The research results show that under the condition of ensuring the material removal rate, it is necessary to reduce the scratching depth of the abrasive grains to lower the contact force of the abrasive grains and to obtain a smoother surface morphology and lower equivalent stress.