Ductile regime turning at large tool feed

Ductile regime turning is a new technology for obtaining a crack-free surface on brittle material. However, the fundamental obstacle for industrial application of this technology is diamond tool wear. This problem is difficult to solve for existing methods of turning with round-nosed tools due to limitation on tool feed. In this paper, ductile regime turning using the straight-nosed diamond tool is proposed. This method enables thinning of undeformed chip thickness in the nanometric range and at the same time provides significant cutting width ensuring plain strain conditions. Adopting a small cutting edge angle enables ductile regime turning at a large tool feed up to a few tens of micrometers. Single crystal silicon is machined and chip morphology and machined surface texture are examined for clarifying the brittle-ductile transition mechanism. Ductile surface with nanometric roughness is obtained and generation of plastically deformed continuous chips is confirmed. (C) 2002 Elsevier Science B.V. All rights reserved.