Potential Energy Sequences of Characteristic Atoms on Basis of Heats of Formation of Disordered Au(subscript (1-x))Cu(subscript x) Alloys (Part 1)

The systematic science of alloys (SSA) is a framework of the total energy and total volume able to be separated. In this paper, the potential energy sequences of characteristic atoms at the central sites of the basic clusters in the fee-based lattice Au-Cu system are calculated from nine potential energy E-functions, through the use of structural unit inversion method and according to CALPHAD assessment for the experimental heats of formation of the disordered Au(subscript (l-x))Cu(subscript x) alloys only at 320 K. According to the potential energy sequences, the composition-ordering degree-dependent potential energy and heats of formation of the Au3Cu-, AuCu-and AuCu3-type ordered and disordered Au(subscript (1-x))CU(subscript x) alloys are calculated at 0 K, and the compositional-dependent critical T(subscript c)-temperatures of the order-disorder transitions are estimated. These results show that the experimental disordered Au(subscript (1-x))Cu(subscript x) alloys may be existed in the short range ordering state, but 4th, 5th and 7th E-functions may be suggested for developing them into the Gibbs energy, enthalpy, vibrational energy, vibrational entropy functions in order to make further choice.