Brittle-Ductile Transition and Its Control in Machining of Monocrystal Silicon

Abstract

This paper describes the basic conditions for the brittle-ductile transition in the ultraprecision machining of brittle materials in order to explain the deformation and fracture mechanism of a sub-surface layer induced by the microinteraction between a tool and a material. The temperature and stress distribution were simulated by a finite element method using a indenter sliding contact model in diamond cutting of monocrystal silicon. From this analysis, the characteristics of high temperature and stress field during the microcutting of brittle materials, and also the deformation and fracture behavior were clearly understood. The stable ductile mode machining of brittle materials is achieved by controlling the depth of cut, cutting speed and lubrication.