Study on Mechanical Properties and Failure Mechanisms of Highly Filled Hydroxy-Terminated Polybutadiene Propellant under Different Tensile Loading Conditions

To study the mechanical properties of highly filled hydroxy-terminated polybutadiene (HTPB) propellant with 90 wt% solid fillers, stress–strain curves under different temperatures (−50 to 70 °C) and strain rates (0.000476 0.119048 s−1) were obtained by uniaxial tensile test. Moreover, obtain glass transition temperature understand effect low on propellant, DMA experiments carried out. On this basis, response laws analyzed, master established. Furthermore, fracture features typical loading conditions SEM, corresponding failure mechanisms analyzed. The results show that maximum strength decreases increasing temperature, while elongation increases at same rate. rate, rate temperature. is lowest a value 0.35 MPa when 343.15 K 0.000476 s−1, which time reaches highest 44%. In terms mechanisms, shows no particle fracture, modes are mainly matrix tearing dewetting.