Localised surface segregation and martensite nucleation in noble metal based ternary alloys

A recent model connecting martensite nucleation with localised surface segregation phenomena is extended to dilute ternary alloys based on -CuZn and -AuCd. Experimental data about composition induced variations of the critical temperature for the onset of martensitic transformation are organised in a coherent fashion by the atomistic Valence Electron Localisation Degree variation model. An analysis of the surface segregation properties of the original and effective alloys involved in micro nucleation events of martensite is performed by a model relying upon charge transfer effects. It is concluded that martensite nucleation may be interpreted in terms of preferential, localised surface segregation events.Preliminary results of the research were presented at the Discussion Meeting on CuZnAl Martensite Shape Memory Alloys, 19–21 June 1984, Leuven, Belgium