INVESTIGATION ON THE THERMAL-MECHANICAL RESPONSE DURING THE PROCESS OF TANTALUM ALLOY EFP FORMATION

The formation of Explosively Formed Projectiles (EFPs) is a complex, multi-physical field interaction process, typically characterized by high temperature, strain, and strain rate. The thermal-mechanical response significantly affects the shape of the EFP and can even cause it to fracture. In this study, the nonlinear dynamic simulation software LS-DYNA was used to simulate the formation of a tantalum alloy EFP. The simulation results for temperature were consisted with theoretical calculations based on adiabatic theory. Temperature and strain rate were included as independent variables to simulate the dynamic tensile behavior of tantalum alloy samples. Stress-strain curves of tantalum alloy were obtained under different loading conditions, and the function of temperature, strain, and strain rate was constructed by introducing the Zener-Hollomon parameter. The relationship between the thermal-mechanical response and the EFP's regional distribution was successfully established, providing a solid basis for the structural design of a tantalum alloy liner in future work.