Study on Grindability of Thermo-Spray Coated Nanophase Materials

摘要

This study is aimed at experimentally investigating grind ability of nanostructured materials coatings and theoretically developing a mechanical model to simulate the machining process of ceramics. Comprehensive microgrinding experiments are designed to study the effects of the grinding process parameters, such as abrasive grit size, wheel bond type, wheel depth of cut, and work piece feedrate, on surface finish, subsurface damage, and residual stresses of these coatings. The correlation between the grinding conditions and surface integrity, surface finish as well as wear performance of ground samples is explored. The glancing Incident Xray diffraction is Introduced to measure the depth profiles of residual stresses In the coatings. The experiment turns out: The effects of the microgrinding process are limited to the surface layer of ground coatings; The wheel depth of cut Is the most Influential parameter In the cup-type grinding; Ductile flow is the dominant material removal mechanism in grinding n-WC/12Co coatings under all grinding conditions used and in grinding n- AI203/13Ti02 at small material removal rate; The residual stresses induced by the microgrinding process are compressive, strongly depend on the grinding direction, and show strong gradient in thickness direction for both coatings.