Improved cemented carbide tool edge formed by solid phase chemical–mechanical polishing

Abstract

When a diamond grinding wheel is used to create the cutting edge of a carbide tool, it induces latent flaws in the tool material. We developed a fixed abrasive wheel for solid phase chemical–mechanical polishing (SPCMP) and successfully sharpened the cutting edge of cemented carbide (WC–Co) tools while removing the latent flaws on the cutting edge. X-ray diffraction and electron backscattering diffraction measurements revealed that the SPCMP method removes latent scratches from the surfaces of WC–Co materials. Further, it can remove latent scratches introduced by the diamond wheel on the cutting edge of WC–Co tools, thus reducing the wear rate and extending their service life, as verified by conducting cutting experiments on Ti–6Al–4V and Inconel 718. Thin-film X-ray diffraction measurements using synchrotron light revealed that the processing strain on the surfaces of Ti–6Al–4V and Inconel 718 machined by the WC–Co cutting tool with SPCMP processing was extremely small when compared with the processing strain in the case without SPCMP processing.