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

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.