Sweeping wave impact on tantalum plate*

The tensile plasticity (TEPLA) model is extended to study sweeping wave impact, where the material undergoing large deformation, pore growth, and failure. We start with the ensemble phase averaging method to derive averaged equations for inhomogeneous material. For a given time and spatial position, it only averages over the material configurations in which the given spacetime is occupied by the specified material. The averaging method leads to the decomposition of the velocity gradient into intrinsic part representing the gradient experienced by the solid material and the plastic part caused by deformations related to slipping planes, void growth, and sliding on the crack surfaces.

To compute large plastic deformation, while accurately tracking the material history Dual Domain Material Point (DDMP) method is employed. The DDMP method uses both Eulerian and Lagrangian descriptions. We use the Eulerian capability to compute the large deformation of the solid caused by a swiping shock wave and the Lagrangian capability to track history dependent plastic pore growth. Numerical results are compared to an experiment to show the needed improvements on both the physical models and numerical techniques.