Compressive Mechanical Properties of Solid Propellant Under High Temperature and Different Strain Rates

ABSTRACT The present study investigates the compressive mechanical behaviour of a newly developed solid propellant under high temperatures and different strain rates. Quasi‐static and dynamic uniaxial compression tests of the energetic solid propellant were conducted under high temperatures and different strain rates. Based on the test results, there exists a significant correlation between temperature, strain rate and the mechanical characteristics of energetic solid propellants. As temperature increases, both compressive strength and compressive modulus of the solid propellants exhibit a decreasing trend. The damage mechanisms of the solid propellant under various loading conditions were systematically analyzed. A thermoviscoelastic constitutive model was established to characterize the mechanical behaviour of solid propellants under various high strain rates and across an extensive temperature range. The multipopulation genetic algorithm (MPGA) was employed to optimize the model parameters. The constitutive model demonstrates excellent applicability in accurately capturing the mechanical responses of both the elastic and reinforcing phases of solid propellants.