Properties and applications of some gold alloys modified by rare earth additions

Abstract

The influence of rare earth (RE) additions on the microstructure and some properties of gold and gold alloys have been studied. RE additions can refine the grain size of gold alloys, but show a tendency to segregation, both dendritic segregation in cast alloys and grain boundary segregation in annealed alloys. For gold alloys, RE additions are generally used in trace amounts or dilute concentrations in order to avoid a large segregation of RE and the potential embrittlement of gold alloys. The experimental results demonstrate that RE additions can inhibit recovery softening, increase the recrystallization temperature and enhance the strength of gold alloys. The strengthening mechanisms of RE additions in gold alloys are discussed. Some gold alloys with RE additions have been developed and their applications are illustrated briefly.