PHASE EQUILIBRIUMS IN THE Tl–Tl₄PbTe₃–Tl₉BiTe₆ SYSTEM

Phase equilibriums in Tl₂Te–Tl₄PbTe₃–Tl₉BiTe₆ (А) system were investigated using DTA, EMF, X-ray phase methods and measurement of microhardness. The T-x diagram of quasi-binary Tl4PbTe3–Tl9BiTe6 system, some internal polythermal projections of system (A) and projections of liquidus and solidus surfaces constructed. It showed that the system (A) is characterized by formation of solid solutions with Tl₅Te₃ type tetragonal structure, except for concentration area which is very abundant (>90 mole %) with Tl₂Te. The stability of the system is broken in areas rich Tl₂Te–metallic phase on the basis of thallium is observed in alloys.