Theory of order-disorder and order-order transformations in binary alloys with B.C.C. lattice—II: Phase diagrams

Abstract

The calculations of the order-disorder phase diagrams and phase equilibrium between the superstructures B2(CuZn), DO 3(Fe 3Al) and B32(NaTl) were carried out by Kikuchi's method with the account of atomic interaction and the short-range order in the first two coordination spheres. The dependence of the phase diagram on the relation of the ordering energy inthe second coordination sphere v 2 to the ordering energy in the first coordination sphere v 1 is discussed. In many respects the results are essentially different from those known earlier and are in agreement with experiment. This gives new opportunities to the classical ordering theory for a quantitative description of some binary systems.