Research On Grinding Of Engineering Ceramics With Innovative Monolayer Brazed Diamond Wheels

Engineering ceramics are now widely used under great and complex demands to produce different parts in many fields such as aviation and aerospace industry, automotive industry, cutting tools manufacturing industry, etc. Because the diamond grinding wheel performance and the related grinding process parameters significantly influence the cost, efficiency and surface integrity, it is helpful to develope the innovative diamond grinding wheel and scientifically to evaluate the performance of grinding wheel for promoting ceramics machining with good quality and high productivity.Depending on the strong joining effects induced by the chemical and metallurgical behavior among the abrasive grains, the filler alloy and the metal substrate and the orderly distributed grains technology, the innovative monolayer brazed diamond grinding wheels with orderly distributed grains are developed. Subsequently the special tools were evaluated in the high performance grinding of engineering ceramics in order to further broaden the application field of the brazing diamond grinding wheels.The main contents in this paper are as follows:1) The innovative monolayer brazed diamond segmented grinding wheels with orderly distributed grains is designed according to the requirements of brazing technique to realize the precision grinding of engineering ceramics. Moreover, on the basis of determined the suitable brazing process, the machining process of the grinding wheel with structural components mainly controlling the rotary accuracy of the wheel and the equal height characteristics of grains is effectively controlled, this kind of fine-grained diamond grinding wheel applied to engineering ceramics is successfully developed.2) The technique foundation conditions of grinding engineering ceramics by the monolayer brazed diamond are elucidated and the mechanism and the critical conditions of brittle–ductile transition are investigated. What's more, the fundamental experimental researches of the ductile mode cutting of zirconia ceramic are conducted and the feasibility of ductile grinding engineering ceramics with the brazed diamond tools is presented. Furthermore, ductile grinding parameters are scientifically optimized based on the mechanism of brittle–ductile transition according to the ordinary precision grinding machine and the high speed grinding machine.3) Grinding performance of the innovative monolayer brazed grinding wheel was investigated based on the grinding and wear experiments. The grinding force and the specific grinding energy of the alumina ceramic and the zirconia ceramic are mainly discussed. The sharpness of the brazed diamond grinding wheel is analyzed based on both the single grain grinding force and the grinding force ratio. The energy dissipation mechanism of the engineering ceramics is elucidated and the brittle–ductile transition exists in the material removal modes when grinding engineering ceramics. Furthermore, the wear experiments for the innovative monolayer brazed grinding wheel are conducted and the wear main form of the grinding wheel is investigated.4) Research on the grinding surface integrity of the two different ceramics is conducted with the fabricated innovative monolayer brazed diamond grinding wheel. The variation law of the surface integrity of engineering ceramics after being ground under the different maximum undeformed chip thickness is discussed from four aspects: surface roughness, residual stress, flexural strength and surface/subsurface damage. Furthermore, the surface integrity in the ductile grinding process is mainly investigated.