Observation and prediction of out-of-plane deformation in CuAlNi

This paper discusses the out-of-plane deformation caused by stress-induced shape memory phase transformations in CuAlNi. Using three-dimensional optical profilometry, the step-like phase transformation is measured and compared to predictions from the crystallographic theory of martensite. By examining the deformation around a notch in mode I loading, it is observed that the martensite plates formed cause the area near the notch tip to displace into the sample. This behavior is an additional constraint on deformation in shape memory alloys.