Order–Disorder Model of Phase Transition in A x B 1− x Binary Systems of F.C.C. Structure

By means of the cluster variation method, and introducing the nearest‐neighbour interaction, a phase diagram of the A x B 1− x binary system with f.c.c. structure is obtained. A calculation of the lattice parameters versus composition is carried out, and the results show that the formation of an amorphous alloy in an immiscible FeCu system could be attributed to the lattice deformation.