Inelastic deformation behavior of PMR-15 high temperature polymer at 316 °C

The strain rate (time)-dependent mechanical behavior of PMR-15 neat resin, a thermoset polymer, was investigated at 316degC. In order to investigate the inelastic deformation behavior of PMR-15, experimental program was designed to explore the effect of prior strain rate on monotonic loading and unloading, and relaxation behaviors. In addition, the recovery of strain at zero stress and the creep behavior following strain controlled loading were examined. The material exhibits positive, nonlinear strain rate sensitivity in monotonic loading and unloading. Early failures occur in the inelastic regime. The recovery of strain and creep response are profoundly influenced by prior strain rate. The material does not exhibit strain rate history effect. The prior strain rate also has a strong influence on the relaxation behavior.