DEFORMATION BY MOVING INTERFACES FROM SINGLE-CRYSTAL EXPERIMENTS TO THE MODELING OF INDUSTRIAL SMA

Microstructure-based micromechanics models have to be developed in ord er to successively predict complex thermomechanical behaviors of shape -memory alloys (SMA). However, a proper implementation of the deformat ion mechanism-motion of internal interfaces in solid state-into the mi cromechanics models of SMA polycrystals is very important. In this wor k, experimental characteristics of the deformation mechanism surveyed from literature data obtained from uniaxial loadings of SMA single cry stals are summarized. Original results of thermomechanical tension/com pression loading experiments on CuAlNi and CuAlZnMn single crystals an d CuAlZnMn polycrystals are also reported. Oriented single crystals ma y transform into different martensitic phases under various orientatio ns of the uniaxial loading axes and sense of the applied stress. This phenomenon is called martensite formation anisotropy and possible cons equences for thermomechanical behaviors of CuAlZnMn polycrystals are s uggested. (C) 1997 Published by Elsevier Science Ltd.