The Influence of Sintering Temperature on Phase Composition and Mechanical Properties of $c$BN-Based Composites with Addition of Vanadium Compounds

The influence of the sintering temperature on the mechanical properties of cBN-based ceramic composites with binders in form of vanadium compounds is investigated by methods of physical material science. Two compositions are selected for the study cBN–VC–Al and cBN–VN–Al with 60% vol. of cBN. Samples are obtained by high pressure high temperature sintering (HPHT) in toroid type apparatus with central hole 30. Sintering is conducted in temperature range of 1600–2450°C under pressure of 7.7 GPa. Sintering in the temperature range of 1600–1850°C induces the beginning of the interaction between components of the mixture and significant change in the elastic properties of the samples in both systems. As found, the maximum values of microhardness are achieved at 2150°C—40 GPa for a system with a carbide binder and 30 GPa in a system with vanadium nitride. The highest level of tool wear resistance during high-speed machining of steels is shown the samples of both groups sintered in the temperature range of 2000–2150°С. (Less)