Dynamic Strength of Copper at High Pressures Using Pressure Shear Plate Experiments

Dynamic Strength of Iron at High Pressures and Strain Rates

“…In particular, the peak transverse velocity is directly related to the strength and flow behavior of iron and thus we determine simulation parameters to match peak velocities of the experimental data. This sandwich configuration and plastically deforming anvil analysis methodology has been successfully validated using various anvil materials on copper [32]. Thus, the key results in this Letter represent the physics of iron and are not from an unknown error in the experimental or analysis method.…”

“…When considering the yield strength scaling with respect to pressure, the SCG model approximates a one-toone relationship between the pressure dependence behavior of the shear modulus and yield strength ½ð1=Y 0 Þð∂Y=∂PÞ ¼ ð1=G 0 Þð∂G=∂PÞ. However, recent experiments on tantalum [38] and copper [32] have shown the yield strength scaling to be 2 and 2.6 times that of shear modulus, respectively. This was based on the decrease of dislocation mobility at higher pressures and the shear modulus scaling of work required to move the dislocations [39].…”

“…Because of plasticity within the anvil material above its Hugoniot elastic limit (HEL), conventional elastic analysis of extracting strength from transverse velocity profiles is not feasible. For this reason, we conduct finite element simulations via ABAQUS/Explicit [31] and match simulated velocities with the experimental measurements [21,32] to extract a material model for the iron sample. In particular, the peak transverse velocity is directly related to the strength and flow behavior of iron and thus we determine simulation parameters to match peak velocities of the experimental data.…”

“…Thus, the key results in this Letter represent the physics of iron and are not from an unknown error in the experimental or analysis method. For a known tungsten carbide material model [32], the only unknowns required to match our experimental velocity profiles are equation of state and strength parameters for iron. For α iron, a Johnson-Cook strain and strain-rate hardening model with temperature softening from Sadjadpour et al [33] was implemented.…”