Ductility-oriented high-speed grinding of silicon carbide and process design for quality and damage control with higher efficiency

Abstract

Grinding of brittle materials is always a removal process of coexisting ductile and brittle removal modes. Ductility-oriented grinding has been regarded as a precision machining pursuit for grinding quality and efficiency. This paper is devoted to investigating ductility-oriented grinding mechanism and process design for quality promotion with a higher efficiency in high-speed grinding of silicon carbide ceramics. The Rayleigh chip thickness model and critical chip thickness model are given to quantitatively calculate the ductile removal proportion. Moreover, the grinding forces and specific removal energy are discussed to reflect the high-speed grinding removal mode. The results show that the increase of wheel speed or decrease of maximum chip thickness could enhance the percentage to a more ductile-oriented removal mode, which will cause a smaller surface roughness with fewer fracture cracks and more plastic removal stripes. Finally, the grinding process conditions for surface roughness below 0.2 μm and ductile removal area higher than 50% are suggested to obtain better surface quality at higher ductile removal and material removal rates.