PHASE-EQUILIBRIA IN CO-ME'C-ME''C ALLOYS .1. SYSTEMS WITH 3-PHASE EUTECTIC EQUILIBRIUM

The phase equilibria are studied in the quaternary systems Co-Me'-Me ' '-C (where Me = Ti, Zr, Hf, V, Nb, Ta) on the sections Co-Tic(0.8)-VC0 .83, Co-TiC0.86)-NbC0.9, Co-TiC0.8-TaC0.82, Co-ZrC0.81-HfC0.94, Co-ZrC 0.81-NbC0.82, Co-HfC0.94-NbC0.82, Co-HfC0.94-TaC0.82, and Co-NbC0.82-T aC0.82. The results of calculations of the structure, phase compositio n, and melting point indicate that on all those sections of the alloys have one type of composition-temperature diagram with one monovariant three-phase eutectic equilibrium.