X-ray diffraction, with sub-ns temporal resolution, was used to measure the lattice parameters of orthogonal planes in shock-compressed single crystals. In spite of a uniaxial compression, along the (400) direction, which reduced the lattice spacing by almost 11% no observable changes occurred on planes having normals which were orthogonal to the shock propagation direction. The results were consistent with simple estimates of plastic strain rates which were based upon dislocation velocity data.

Anomalous Elastic Response of Silicon to Uniaxial Shock Compression on Nanosecond Time Scales. A.Loveridge-Smith, A.Allen, J.Belak, T.Boehly, A.Hauer, B.Holian, D.Kalantar, G.Kyrala, R.W.Lee, P.Lomdahl, M.A.Meyers, D.Paisley, S.Pollaine, B.Remington, D.C.Swift, S.Weber, J.S.Wark: Physical Review Letters, 2001, 86[11], 2349-52