Ductile Cu–Al–Mn based shape memory alloys: General properties and applications

Abstract

Polycrystalline Cu–Al–Mn shape memory alloys (SMAs) with a low degree of order of the β (L2 1 ) phase show excellent ductility and exhibit shape memory (SM) properties such as superelasticity, the one way memory effect and the two way memory effect based on martensitic transformation. These SM properties can be greatly enhanced by controlling microstructural factors such as grain size and texture by thermomechanical treatments. In the present paper, the SM properties of ductile Cu–Al–Mn based SMAs and microstructure control to obtain excellent SM characteristics are reviewed. Furthermore, an example of the application of Cu–Al–Mn based SMAs to a guidewire for medical use is also presented.