Thermomechanical characterization of phase transformation surfaces for thin SMA wires

The phase transformation of thermal shape memory alloys (SMAs) can be described by surfaces in a temperature-stress-strain space. A novel experimental technique for the thermomechanical characterization thin SMA wires allows to scan these with high resolution. Each run uses sequence conditions traverse on different path from “full martensite” austenite” and vice versa. At all times, stress strain are kept within limits specified use wire actuators. is heated externally through silicon oil bath, which ensures controlled homogeneous temperature specimen. setup designed minimize impact large variations measurement results. Experimental results shown both mechanical contraction electrical resistance, each forms consistent transformation. Measurements external heating bath compared air.