Modelling and material design of SMA polymer composites

Material design has recently become one of the key topics in the development of smart adaptive composites. In particular, different material constituents of the hybrid polymer composites with embedded Shape Memory Alloy elements (SMA composites) have to be combined and positioned in such a way that predetermined functional properties are obtained. Due to the complexity arising from the inherently nonlinear and hysteretic thermomechanical response of SMA elements, modelling of the functional behaviour of SMA composites has become an indispensable part of the SMA composite technology. In this paper, design of SMA polymer composites using a recently developed SMA composite model is demonstrated. The simulations carried out in a preliminary stage of the smart composite design help to find optimal material parameters of the SMA wires (Young's modulus and coefficient of thermal expansion of austenite and martensite. transformation temperature, strain, hysteresis, entropy. etc.) and of the polymer matrix (longitudinal Young's modulus, coefficient of thermal expansion), as well as optimal composite fabrication parameters (layout of the composite, volume fraction of wires, prestrain given to the SMA wires when hybridising it with the matrix).