Factors affecting energy absorption of a plate during shock wave impact using a damage material model

Abstract

This thesis examines the influences of five factors on the strain energy at failure of metallic alloy plates during a shock wave impact. The five factors are material type, initial damage, boundary conditions, plate thickness, and plate temperature. The finite element simulation matrix was developed using a statistical design of experiments (DOE) technique. The Eulerian hydrocode CTH was used to develop the pressure histories that were input into the finite element code Abaqus/Explicit, which implemented the Mississippi State University internal state variable (ISV) plasticity-damage model (DMG). The DMG model is based on the Bammann-Chiesa-Johnson (BCJ) ISV plasticity formulation with the addition of porosity and the void nucleation, growth, and coalescence rate equations that admit heterogeneous microstructures. Material type and thickness were the primary influences on the strain energy at failure, and the materials studied, magnesium and aluminum, showed two different failure mechanisms, tearing at the boundaries and spalling, respectively.