Phase equilibria in Co-rich region of Co-Ti-Ta system

The phase equilibria in Co-rich region of Co-Ti-Ta system were studied. The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 °C. The Co3Ti phase possesses a solubility of Ta higher than 10%, and the addition of Ta stabilizes the Co3Ti phase. The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000, 1 100 and 1 200 °C were constructed according to the result.