DYNAMIC COMPRESSION OF POROUS TUNGSTEN

Data are presented from a study conducted to examine the shock-loading behavior of a sintered porous tungsten with a density of 12.64 g/cm3 (corresponding to 65.3% of the density of solid tungsten). The experiments were performed by using a gas gun and high explosives. Hugoniot data obtained in the stress range between about 12 kbar and 1 Mbar indicate that compression of the porous material to a fully compacted state is essentially complete at 50 kbar. Above this level, a predicted Hugoniot, calculated from the Hugoniot of solid tungsten by using the Mie-Grüneisen equation of state, agrees well with experimental data. Below 50 kbar the Hugoniot of the porous tungsten deviates from the predicted Hugoniot increasingly with decreasing stress. Propagated wave profiles at lower stresses are characterized by two precursor waves, the faster being a low-level wave (∼0.2 kbar) traveling at about sonic velocity in the porous tungsten (∼3.04 mm/μsec). The slower precursor has an amplitude of 2.73 kbar and travels at 2.02 mm/μsec. The behavior of this porous tungsten is analogous to the behavior of sintered porous copper previously studied. © 1969 The American Institute of Physics.