A computational investigation of adiabatic shear plugging based on thermo-viscoplastic instability

1619-6937

Springer Online Journal Archives 1860-2000

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Physics

Summary The adiabatic shear plugging of a titanium alloy target impacted by a steel projectile is numerically studied by a recently developed dynamic Lagrangian finite element code ETVP. The elastic-plastic wave propagation effect in the long projectile is taken into account. The rate-dependent behaviour of the titanium alloy target is also taken into consideration by using a thermo-viscoplastic constitutive equation. Moreover, the adiabatic shear failure criterion with two control variables (both strain and strain rate) based on thermo-viscoplastic constitutive instability of materials is generalized to three-dimensional stress states and incorporated into the code. The results clearly show the developing process of adiabatic shear plugging of the target including the initiation of the localization, the widening and deepening of adiabatic shearing zone, and finally the forming of a plug. The numerical results for the residual velocities are found to be in good agreement with those measured experimentally. The corresponding energy relation in the plugging process is then analyzed from this new plugging model.

Electronic Resource