Stepanenko A. The features of structural state and physical-mechanical properties of composite diamond-SiC

A structure of a number of diamond polycrystalline materials was investigated. Stress-strain state of diamond-SiC composite is determined by pressure of sintering and mismatch of the elastic constants of phases. This state brings to high operation performances of material since SiC is exposed to compressive stresses and diamond - tensile stresses. Microstresses in diamond are arisen from presence of pseudomacrostresses. Accounting for the structure of composite enables to increase an accuracy of forecast of modulus of elasticity. Wetting of natural diamond and composite diamond-SiC by metallic melt, which are a background for production of commercial solders, is similar. A presence of SiC in the composite brings to insignificant impairment of wetting of the composite diamond-SiC if compare with single crystal of diamond. In terms of the obtained results, the optimized microstructure of composite diamond-SiC was proposed and obtained at high pressure (7-8GPa) and temperature (1700-1800 C). This microstructure provides a high wearresistance and thermalstability. The main regularities of structure formation of this material versus time of isothermal holding and structural state of initial diamond powders were specified.