Influence of chemical composition and manufacturing conditions on properties of NiTi shape memory alloys

This work presents a study of the production of NiTi shape memory alloys and investigates the optimum conditions for tungsten addition and heat treatment. For the present investigation some specimens were prepared by vacuum induction melting with various compositions of NiTi and NiTi(W) in different crucibles and moulds. After rolling and heat treatment at various temperatures, tensile tests, hardness tests, and scanning electron microscopy with energy-dispersive X-ray spectrometry were performed. Finally the appropriate manufacturing conditions and chemical compositions for suitable shape memory alloys with reliable properties were obtained.