MULTI-3D MODELING OF THE LIQUIDUS AND IMMISCIBILITY SURFACES IN THE Cu–Pb–Te SYSTEM

Based on thermodynamic calculations and analysis of experimental literature data the fields of the primary crystallization of the phases, the types and coordinates of non- and monovariant equilibria in the Cu–Pb–Te system are determined. It has been revealed that the ternary compound is not formed in the system, and in the solid state it is divided into subsystems with the participation of lead telluride: Cu–PbTe–Pb, Cu–Cu2-xTe–PbTe, Cu2-xTe–Cu5Te3–PbTe, Cu5Te3–Cu4Te3–PbTe, Cu3-xTe2–CuTe–PbTe, CuTe–Te–PbTe. The projection of the liquidus surface Cu–Pb–Te is determined. On the basis of phase diagrams of the boundary binary systems and the limited number of DTA data of the ternary system by using the OriginLab program, equations are obtained for calculating and 3D modeling of the PbTe, CuTe, Cu2-xTe, Cu3-xTe2, and Cu5Te3 crystallization surfaces and the surface of the liquid immiscibility in the Cu–Pb–Te system. There are regions of immiscibility for the liquid phase from the side Cu–Cu2-xTe and Cu–Pb. With an increase quantity of the third component, the critical temperature immiscibility decreases. Defined in the work 3D model for the system Cu–Pb–Te keeps the corresponding analytical function and table data in the form of matrices