Efficiency of Hybrid Sintering Technology for Cemented Carbide Diamond-Containing Composites with Impregnation, Including Thermal Diffusion Metallization of Diamonds

Abstract

For the enhancement of chemical and mechanical adhesion of natural diamond particles with a hard-alloy matrix during the synthesis of diamond-abrasive composites the hybrid technology which combined in one technological process the thermal diffusion metallization of diamond particles and sintering by the developed scheme of the self-dosed impregnation is proposed. This technology does not include a reheating of the metallized coating that causes its destruction and enhances graphitization of diamond thus limiting the application of metallization method for improvement of diamond retention and creation of high-functional composites for diamond tools. Formation and preservation of adhesion-durable metallized coating is confirmed by experiments simulating the conditions of high temperature interaction of diamond with a carbide-forming metal and a hard-alloy matrix during the sintering of special samples using the regimes of developed technological process. The structural and phase state of the transition zone is studied by scanning electron microscopy, X-ray structure analysis and X-ray phase analysis of the partition surfaces of the contact zone between the diamond and the matrix obtained by tensile testing of special samples. Comparative service properties tests of prototype and control samples of diamond dressers confirmed efficiency of the developed hybrid technology for the creation of diamond tools.