The antioxidation coating of diamond and the strengthening of ceramic grinding tools with a glass-ceramic layer as part of the bonding material

Abstract The main area of industrial application for diamond is the manufacture of grinding tools. The market offers tools made of diamond grain with metal or resin as the bonding material. The production of ceramic-bonded (sintered) diamond tools is very low because of the easy oxidation of diamond in the sintering process. In this article we describe a two-stage ceramic-diamond tool manufacturing process where the application of glassy (molten) conventional binder is preceded by masking the grain with a glass-crystalline material or low melting point glaze. This process enables the production of porous diamond tools with ceramic binding material, which greatly extends the range of their application and facilitates tool cooling in the machining process. The glass-crystalline coating also improves the strength of the grain and of the diamond grain-glassy binder bond.