The influence of model parameters and of the thermomechanical coupling on the behavior of shape memory devices

Shape memory materials (SMM) are receiving increasing attention for their use in applications that exploit their dynamic behavior. A thermomechanical model for devices with pseudoelastic behavior has been proposed in previous works [11] (Bernardini and Pence, 2005) [15] (Bernardini and Rega, 2005). The model takes into account several aspects of SMM behavior by means of seven model parameters. In this paper the effect of each parameter on the non-isothermal rate-dependent behavior of the device is studied, by paying particular attention to the effect of the thermomechanical coupling. Some overall synthetic indicators of the behavior of the shape memory device are defined in terms of the model parameters. By evaluating such indicators, a lot of information about the mechanical, thermal and thermomechanical effects on the device behavior can be gained before computing explicitly the response of the shape memory oscillator. The present work may provide a guide for the proper utilization of the model for the investigation of the dynamic response. (C) 2009 Elsevier Ltd. All rights reserved.