Characterization of the mechanical properties of ultra‐fine grained NiTiCr‐wires

Abstract

Abstract NiTiCr is used in medicine for retriever devices, dental‐ and guide wires [1–3]. Very little has been published in literature about this ternary NiTi‐alloy. In the present work, the mechanical properties of NiTiCr shape memory alloy (SMA) wires (0.25 wt.% Cr) in the as‐received condition and after a number of different heat treatments were studied. The surface quality of the wires was examined, because it is known that the surface condition has an influence on fatigue life. Mechanical uniaxial loading‐unloading tensile and cyclic tests were performed. Bending‐rotation fatigue (BRF) tests at higher rpm‐levels were conducted in air and in oil. This is important with regard to possible applications, where NiTiCr might be used as a structural component.