On the machinability for alumina green compact (part 6) -cutting force on orthogonal cutting-

摘要

In recent years, many ceramics have been developed for the uses to mechanical and electronic parts. The strength of alumina ceramic pieces is influenced by the residual crack of the machined surface which generates due to the action of force on the cutting process. The purpose of the study is to clarify the cutting mechanism of alumina green compact by the orthogonal cutting test. The cutting mechanism is discussed from a view point of the relation between specific cutting force and depth of volume or chamfer angle. In the cutting test by a new type testing machine, the cutting conditions are cutting speed 0.8m/s and depth of cut 0.05mm to 0.4mm. The chamfer angle of tool shape was varied from -20° to 5° in grinding. The main results obtained are follows; (1)The specific cutting force of the alumina green compact is affected by depth of cut volume and chamfer angle. (2)In small depth of cut, main crack propagates to inside of a granule, while other crack propagates along grain boundary in large depth of cut.