Phase Equilibria in the Sb2Te3-InSb System

The phase diagram of the (Sb2Te3)(100-x) -InSb (x) system was determined based on x-ray diffraction (XRD) analysis, differential thermal analysis (DTA), and microhardness and density measurements. An intermediate compound with composition Sb2Te3 center dot 2InSb was formed as a result of syntectic reaction, melting incongruently at 553 A degrees C. This compound has tetragonal lattice with unit cell parameters of a = 4.3937 , b = 4.2035 , c = 3.5433 , alpha = 93.354A degrees, and beta = gamma = 90A degrees. Sb2Te3 center dot(2 + delta)InSb (-1 aecurrency sign delta aecurrency sign +1) and (Sb2Te3)(100-x) (InSb) (x) (90 aecurrency sign x aecurrency sign 100) solid solutions exist in the investigated system, based on the intermediate compound Sb2Te3 center dot 2InSb and on InSb, respectively. Also, two invariant equilibria exist in the system, with eutectic point coordinates at compositions of x = 60 and x ae 85 mol% InSb and eutectic temperatures of T (E) = 541 and T (E) ae 501 A degrees C, respectively.