Analysis of nonlinear mechanical behavior of resin materials at low and medium strain rates

Commonly used thermoset/thermoplastic continuous fiber‐reinforced composites have an isotropic failure strain of no more than 0.1 and deformation under gas pressure impact loading in the low to medium strain rate range (). In order to accurately grasp the load carrying capacity of the composite material under this condition and predict the damage failure behavior, experimental analysis and finite element study of the nonlinear mechanical behavior of the resin before damage under low and medium strain rate loading are carried out in this article. Based on the linear function of compressive stress and logarithmic strain rate of the resin material, the elastic–plastic principal structure related to the strain rate of the resin material is established. The mechanical behavior of the resin material at low and medium strain rates was obtained by writing the VUMAT subroutine for the numerical finite element simulation of the test conditions, and the good agreement with the experimental results proved the accuracy of the prediction of the mechanical behavior of the resin material at low and medium strain rates by this intrinsic model.