Shock Compression of Aluminum Single Crystals to 70GPa: Anisotropic Mechanical Response

To examine the mechanical anisotropy of aluminum crystals at high stresses, Al single crystals were shock compressed along the [100], [110], and [111] orientations to peak stresses up to 70 GPa. Laser-interferometry was used to monitor the propagating wave profiles and, as expected, a single wave structure was observed in all cases. Shock velocities and particle velocity histories including the unloading profiles were measured for all three crystal orientations. Our results showed that a common curve can be used to represent the Hugoniot for all three orientations. However, variations were observed in the longitudinal sound speed (onset of release) for the different orientations. These differences will be discussed along with a comparison of the single crystal results with comparable results on 1050 aluminum. Work supported by DOE/NNSA.