Effect of alloying constituents on the martensitic phase formation in some Cu-based SMAs

The paper discusses the attempt made to improve upon the transition temperatures and amount of martensite formation in Cu-Al alloys with alloying additions of Mn, Ni and Zn in varying proportions and combinations. The alloys have been subjected to heat treatment cycles to improve upon the microstructure and precipitate the required martensite phase. The effect of these ternary and/or quaternary additions has been studied on the phases precipitated through micro-structural analysis and X-ray diffraction and Differential Scanning Calorimetric studies. The findings confirm the possibility of improvement on the shape memory properties like martensite formation, higher transitions temperatures and longer retention in selected alloys based on the properties exhibited through proper alloying additions and heat treatments. (C) 2014 Brazilian Metallurgical, Materials and Mining Association. Published by Elsevier Editora Ltda.