A preliminary investigation of the effect of post-deposition polishing of diamond films on the machining behavior of diamond-coated cutting tools

Abstract

The development of deposition technology and applications of diamond-coated cutting tools for machining abrasive materials has now reached a stage where viable cutting tools and machining techniques will soon be a commercial reality. Some early reports in the literature have indicated that polishing of diamond coatings may provide certain benefits in terms of reduction in cutting forces and/or improvement in surface finish of the machined component. The benefits of a polished tool are well known in the industry, as evidenced by the use of polished polycrystalline diamond and cemented carbide tools in the machining of non-ferrous materials. The present work was undertaken to investigate polishing of diamond-coated cutting tools and to study the effect of polishing on the machining behavior of such tools. In this paper we report some preliminary results obtained with polished, diamond-coated cemented carbide cutting tools in the machining of Al-Si alloys. The results suggest that polishing of diamond coating allows more efficient cutting owing to improved cutting edge geometry, leading to a reduction in cutting forces and improved chip flow during machining.