Hugoniot Equation of State Measurements for Eleven Materials to Five Megabars

Abstract : An experimental technique is utilized in which a light-gas gun is used to launch flat impactor plates to high velocities (approximately 8 km/sec) at specimens suspended at the muzzle of the gun. Impact-induced shock waves at pressures to approximately 5 megabars are recorded and are used to determine the shock state in the specimen. The ability to launch unshocked, stress-free flat plates over a wide and continuous velocity range, coupled with the ability to launch impactor plates of the same material as the target, results in hugoniot measurements of relatively high precision. Measurements were made on Fansteel-77 (a tungsten alloy), aluminum (2024-T4), copper (OFHC, 99.99%), nickel (99.95%), stainless steel (type 304), titanium (99.99%), magnesium (AZ31B), beryllium (S- 200 and I-400), uranium (depleted), plexiglas, and quartz phenolic. The results are compared with those of other researchers. Deviation from linear shock velocity - particle velocity was found in aluminum beginning at approximately 1. 0 megabars, probably attributable to melting in the shock front.