Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94550, USA.
Phys Rev Lett. 2018 Jun 29;120(26):265502. doi: 10.1103/PhysRevLett.120.265502.
We have used femtosecond x-ray diffraction to study laser-shocked fiber-textured polycrystalline tantalum targets as the 37-253 GPa shock waves break out from the free surface. We extract the time and depth-dependent strain profiles within the Ta target as the rarefaction wave travels back into the bulk of the sample. In agreement with molecular dynamics simulations, the lattice rotation and the twins that are formed under shock compression are observed to be almost fully eliminated by the rarefaction process.
我们使用飞秒 X 射线衍射研究了激光冲击纤维织构多晶钽靶，因为 37-253 GPa 的冲击波从自由表面爆发出来。当稀疏波返回到样品的主体时，我们从 Ta 靶中提取出与时间和深度相关的应变分布。与分子动力学模拟一致，观察到在冲击波压缩下形成的晶格旋转和孪晶几乎完全被稀疏过程消除。
