PREDICTABLE BEHAVIOR OF SMART MATERIALS (CU-ZN-AL SMA)

Reliability is a critical word in industrial applications of Shape Mem ory Alloys. Accurate and reproducible transformation hysteresis cycles and internal loops were obtained in single crystals using a high reso lution automatized equipment. From a mechanical model formulated for a single martensite plate, the shape of the hysteresis cycle is obtaine d by generalizing the representation to N plates. The observed time ef fects on the hysteresis loops related to diffusion processes were also taken into account. It allows to explain the martensite recoverable c reep and the micromemory effects. Also, the room temperature effects o n the parent phase (for instance, summer to winter) acting over the tr ansformation temperature are quantified.