PREDICTION OF GLASS-FORMATION COMPOSITION RANGES FOR MULTICOMPONENT MELTS WITHIN THE CALPHAD METHOD

Abstract

Theoretical bases of calculation of metastable phase transformations with the participation of supercooled multicomponent melts within the framework of CALPHAD-method are considered. A database of the parameters of the models of the thermodynamic properties of the phases of the Cu–Ni–Ti–Zr–Hf system for performing such calculations is presented. Excess term of Gibbs energy of liquid alloys is described using the model of the associated solution, and bcc and fcc solid solutions –with a mathematical model with Redlich-Kister polynomials. The diagrams of metastable phase transformations with the participation of supercooled liquid alloys and boundary solid solutions are calculated. The concentration regions for obtaining rapidly quenched and bulk amorphous alloys of three-, four- and five-component alloys of Cu–Ni–Ti–Zr–Hf system are theoretically estimated.