Influence of Strain Rate and Temperature on Compressive Properties and Energy Absorption Efficiency of Expanded Polystyrene and Flexible Polyurethane Foam

In this work, large deformation compressive experiments of expanded polystyrene foam (EPS) and flexible polyurethane foam (FPUF) at low temperature (-20 °C) and room temperature (20 °C) with strain rates ranging from 1 s-1 to 100 s-1 were performed using high speed material test machine. According to the experimental results, both EPS materials and FPUF materials show the stress features of the wide platform, and the mechanical properties and the cushioning energy performance of EPS are far better than the FPUF. The testing results indicate the yield strength, plateau stress and energy absorption efficiency of EPS and FPUF increase with strain rate, and the properties at low temperature are higher slightly than that of room temperature. However, the efficiency of the two material buffer absorption is only related to the material itself. The strain rate and external temperature do not affect the best energy absorption efficiency of the material. Finally, on the basis of the experimental results, combine the Sheerwood-Frost model framework, establish the relationship between EPS materials and FPUF materials stress and strain, strain rate, temperature and other variables. This can provide accurate material attributes for simulation analysis.