Simulation of mechanical properties of HTPB-based propellant by a viscoelastic spring lattice model

An improved lattice spring model extended by viscoelastic part using the Maxwell model was applied to predict the mechanical properties of HTPB-based solid propellants. The influence of both strain rate and temperature on the maximum elongation of HTPB-based propellants was quantitatively analyzed by simulating the uniaxial tensile test, as well as the process of crack development during tensile loads. The results show that the maximum elongation of HTPB-based propellant decreases as a power function along with the linear increase of strain rate. In contrast, the maximum stress increases as a power function. Increasing the temperature linearly, both the maximum stress and the maximum elongation decrease as a power function.