Mechanical properties of Ti-50(Pt,Ir) high-temperature shape memory alloys

Abstract

To develop high-temperature shape memory alloys, Ti-50(Pt,Ir)mol% compounds are noted because of their martensitic transformation from B2 to B19(2H) or 4H(4O) structures above 1273K. A thermal expansion measurement and loading-unloading compression test were performed for Ti-50(Pt,Ir) to determine if the shape memory effect or superelasticity was shown. The thermal expansion measurement indicated the shape recovery in some of the compounds. The maximum shape recovery was about 4% by reheating at the above martensite transformation temperature after a loading-unloading compression test. Superelasticity was also observed in ternary compounds. The potential of Ti-50(Pt,Ir) as a high-temperature shape memory alloy is discussed. © 2006 The Japan Institute of Metals.