On the Machinability for the Alumina-Green Compact (Part 4th)

Surface Roughness and Bending Strength

Abstract

In recent years, many ceramics have been developed for the uses for mechanical or electronic parts. The high strength ceramics is necessary for the world of engineering materials. The cutting of the alumina green compact was carried out by a lathe with the condition of the cutting speed 100m/min. The purpose of the study is to clarify relation between surface roughness on the surface of green compact and bending strength of the ceramics. The bending experiment on the ceramics is discussed and then bending strength and the fracture energy were investigated. The main results obtained are as follows; (1) The true bending strength of the alumina ceramics is affected by the surface roughness of the alumina green compact. (2) The fracture energy was 30J/m² in the case of the surface roughness of 5μm.