Subsurface damage in high-speed grinding of brittle materials considering kinematic characteristics of the grinding process

Abstract

Subsurface damage (SSD) induced during abrasive grain machining process strongly influences the mechanical strength and subsurface quality of the brittle components. Therefore, it is meaningful to study the relationship between SSD and grinding parameters. The methods of theoretical analysis, numerical simulation and experimental testing are used to analyze the SSD of brittle materials in high-speed grinding. The results of numerical simulation are consistent with those of theoretical analysis and experimental testing, which indicates that the present numerical method is reasonable. The investigation focuses on the effects of wheel speed, grinding depth, and apex angle of the abrasive grain on the SSD of brittle materials. It shows that when maximum undeformed chip thickness (M-UCT) is greater than the critical thickness of brittle fracture, the material removal is mainly in the brittle mode. A high wheel speed is beneficial to achieving a good subsurface quality. However, under certain conditions, an ultra-high wheel speed with quite small grinding depth is not helpful in SSD control. Due to the kinematic characteristics of the grinding process, the effect of grinding depth on SSD is weaker than that of wheel speed and a smaller abrasive grain is of advantage to subsurface quality. In addition, the grinding force is one of the major factors influencing the subsurface quality.