Constitutive Model of NEPE Propellant Based on Deformation Heat

Abstract

Aiming at the deformation heat phenomenon of nitrate ester plasticized polyether(NEPE)propellant under impact load,the temperature rise function under impact load was obtained based on the heat conduction theory. Due to the problem that the mechanical properties of solid propellants is temperature-dependent,a new viscous-hyperelastic constitutive model considering deformation heat was proposed. The split hopkinson pressure bar(SHPB)tests of NEPE propellant were used to obtain parameters and verify the constitutive model. The result shows that the proposed model can predict the true stress-engineering strain curve well under high strain-rates,and the softening effect of heat caused by impact load on the polymer should be considered while studying the constitutive model of polymer under impact load.