Shape recovery mechanism observed in single crystals of Cu-Al-Ni shape memory alloy

摘要

Micromechanism of the shape recovery process is optically observed in single crystals of the Cu-Al-Ni shape memory alloy. Formation of X and -interfaces (interfacial microstructures with two intersecting habit planes) is documented, both in a thermal gradient and during a homogeneous heating. The observed growth mechanisms (i.e. mechanisms of nucleation and growth of the twinned structures) are described and analysed. Weakly non-classical boundaries between austenite and two crossing twinning systems are also documented.