Critical assessment of copper–gold–silver ternary system

Abstract

A critical assessment has been made of the phase equilibria of the Ag–Au–Cu system. An introductory section summarises the main features of the ternary equilibria. Phase separation occurs in the Ag–Cu system and ordering reactions in the Au–Cu system. In the ternary system the separation of disordered Ag-rich and Cu-rich phases begins at 800°C, whereas the equilibria associated with ordering reactions in the Au-Cu system occur at temperatures below 400°C. Detailed consideration is given to the liquidus, solidus, and solvus surfaces and to the low temperature equilibria in which ordered phases play a major role. An interpretation of the current data is summarised in a proposed reaction scheme for the Ag–Au–Cu system.