Numerical design of shape memory polymer composites with temperature-responsive SMA fillers

Shape memory polymers (SMPs) are stimuli responsive materials that can recover large deformations when heated above their glass transition temperatures. However, at elevated temperatures, SMPs exhibit low modulus and strength and thus, are not suitable for applications where high stiffness or recovery stress is required. In this study, shape memory polymer composites are designed numerically by inserting shape memory alloy (SMA) particles into SMP matrices. The SMP matrix is modeled with Ogden strain energy function and the SMA filler is modeled with the Lagoudas' model. These two material models are linked together through a finite element program to simulate the responses of SMA-SMP composites. The SMA-SMP composites are designed with selected filler contents (0-50 wt%) and their mechanical responses are simulated at temperatures from 18 °C to 55 °C. Overall, the mechanical properties of SMA increase as temperature increases, which are complementary to those of SMP. Compared to conventional fillers, SMA is more effective in enhancing the matrix material due to its unique temperature responsive microstructure and mechanical properties.