Instrumented tensile-impact test method for shape memory alloy wires

摘要

New instrumented tensile-impact test method is proposed for the characterization of shape memory alloy wires in the strain-rate range from 1 to 10~2 s~(-1). The force and the velocity evolution during the impact are registered and, based on these curves, the stress-strain response at impact may be obtained. This method is able to measure strain-rate dependent parameters, such as the direct and reverse stress-induced martensitic transformation stresses or the dissipated energy. Moreover, the accuracy of properties measured with this method, such as the Young's modulus of the austenitic phase or the permanent strain after load-unload deformation, is higher than those calculated exclusively from the integration of the force-time curves.