Research on effect of the pad material on stress of the explosive charge bottom during launching artillery ammunition

Using the generalized Maxwell visco-elastic constitutive model, the stress changes of the warhead explosive charge under high axial overload condition was simulated numerically by finite element method. The influence of Poisson's ratio and elastic modulus parameters of the pad material on the Von Mises stress of the explosive charge bottom was analyzed. The results show that when the elastic modulus of the pad is small, its Poisson's ratio is inversely proportional to the peak stress of the explosive charge bottom, while when the elastic modulus is large, its Poisson's ratio has almost no effect; with the increase of the elastic modulus of the pad, the stress of the explosive charge bottom first decreases and then increases; compared to metal materials and flexible materials, engineering plastic gaskets have a better effect on reducing the peak stress of the explosive charge bottom.