Empirical estimates of shock compression parameters for porous materials

The empirical relation $D=A+BU$ is known to be valid for shock waves of medium intensity, where $D$ is the propagation velocity of the shock front, $U$ is the mass velocity of the substance, and $A$ and $B$ are constants depending on the porosity of the material $k$. In this paper, the experimental data are analyzed to suggest the form of the functions $A(k)$ and $B(k)$ and to determine the parameters involved in these functions for $\mathrm{Al}$, $\mathrm{Bi}$, $\mathrm{Cu}$, $\mathrm{Fe}$, $\mathrm{Mo}$, $\mathrm{Ni}$, $\mathrm{Ta}$, and $\mathrm{Zn}$.