Dynamic behavior of copper under extreme loading rates

Metals subjected to extreme loading rates exhibit behavior that is characteristics of a thermodynamically open system characterized by exchanging energy due to dislocations traveling long distances with a nearly sonic velocity. The thermodynamic openness is rarely observed in solids; therefore the mean-field theories of nonlinear continuum dynamics often provide sufficient representation of the solid behavior. These theories describe the deformation and damage processes with the use of constitutive models. In addition, an equation of state (EOS) that couples high hydrostatic pressure and changes in mass density and temperature is formulated. Difficulties arise when a metal is subjected to extreme loading. Then, the material experiences a mesoscale excitation coupled with velocity fluctuations and a non-negligible entrapment of kinetic energy.