Numerical simulation of polymers at low and moderate strain rates

The mechanical behavior of amorphous polymers and semicrystalline polymers is modeled using finite element analysis (FEA) through user material subroutine VUMAT in ABAQUS/Explicit. The DSGZ constitutive model is implemented using radial return method through user material subroutine VUMAT written in Fortran language. The finite element simulations are done for amorphous polymers called polymethyl-methaacrylate (PMMA) and polycarbonate (PC) and for semicrystalline polymer called Polyamide 12. The FEA prediction using DSGZ model is able to capture elasticity, yield, strain softening and strain hardening in case of amorphous polymers and elasticity, yield and strain hardening behavior in case of semicrystalline polymers. The numerical FEA simulations are done for PMMA for low strain rates of 0.0001 s−1, 0.0005 s−1 and 0.001 s−1 with temperatures of 296 K and 323 K and for PC with the same strain rates as PMMA and temperatures of 296 K and 348 K. Similarly, FEA simulations are done for Polyamide 12 for low to moderate strain rates of 0.001 s−1, 0.1 s−1 and 100 s−1 for temperatures of 300 K, 273 K and 260 K respectively. This study can be used to design various products/structures with these materials used in various service conditions of different strain rates and temperatures using finite element simulations. The FEA simulations are able to capture the behavior of material with higher stresses for higher strain rates and lower stresses for lower strain rates and it showed higher stresses for lower temperatures and lower stresses for higher temperatures. The FEA prediction results and statistical data shows a close match with experimental data and G'Sell Jonas model curves.