Characterization and modeling of the strain-rate, temperature and pressure dependence of the deformatio nof a highly crosslinked aerospace grade epoxy resin

The non-linear behavior of the RTM6 aerospace grade epoxy resin is characterized and modeled by addressing the effects of strain-rate, temperature and hydrostatic pressure. The elastic-plastic constitutive model is based on a simple pressure dependent modified Von Mises yield criterion. A hardening function incorporating pre-upper yield non-linearity, softening and re-hardening is developed. Strain-rate and temperature dependences of the true stress-strain curve are introduced via the coefficients of the hardening function. The constitutive model is selected in order to be directly applicable with the standard distribution of the general purpose finite element software Abaqus, without the need for coding a user defined material subroutine. The introduction of the identified model in the current engineering practice is thus straightforward and will facilitate the use of the identified mechanical behavior of RTM6 in numerical multi-scale analyses of composites.