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We report on a pulsed power experiment performed at the Los Alamos National Laboratory Pegasus facility which was designed to measure material flow at metal interfaces driven to high relative velocities. Material motion at and near four flat Ta/Al(6061) interfaces was measured using flash radiographic techniques. A series of fine Pb wires (407 micron diameter) was implanted in the Al normal to the interfaces. The motion of these markers under shock loading provided a picture of material motion in the Al interfacial region. The surface roughness of the interfaces was varied between 32 and 125 micro-inches. We discuss the implications of these measurements for constitutive models of high speed friction and interfacial morphological change. [ABSTRACT FROM AUTHOR]

Experiments on the Pegasus pulsed power facility have investigated material failure and the growth of sinusoidal perturbations machined on the free inner surface of both A1 1100 and A1 6061-T6 samples undergoing shocked acceleration. The material behind the free surface exhibits massive microspall resulting in a volume of low-density material. Rapid pattern growth in the failed material and subsequent pattern growth on the surface, including jetting in some cases, were seen. Shock pressures were 15 GPa and 50 GPa. [ABSTRACT FROM AUTHOR]