A Discussion on Removal Mechanisms in Grinding Polycrystalline Diamond Available to Purchase

In this paper, the removal mechanisms in grinding polycrystalline diamond (PCD) with vitrified bonded diamond grinding wheels are discussed fundamentally. After a short review about the history of diamond machining, the author summarizes the state of the art in PCD grinding and thus deduces gaps and a deficit in research. In order to analyze occurring removal mechanisms in PCD grinding, tool grinding tests were carried out. For the experimental investigations a conventional tool grinding machine has been modified in order to withstand process loads. Subsequent to the tests, the surface integrity of ground PCD inserts has been analyzed in detail for the first time. Therefore, focused ion beam (FIB) preparation, which has minimum invasive influence on the sub surface, was applied in order to get an insight into the substrate. Gained lamellae have been analyzed with transmission electron microscopy (TEM). The drawn conclusion questions solely ductile or brittle behavior as removal mechanisms. With reference to simulation researches about polishing diamond with diamond, alternative removal mechanisms should be regarded as well. Both, thermal and mechanical process loads might lead to thermo-physical and chemical effects on a microscopic scale which influences the material removal even in grinding.