Open AccessInvestigations into rapid uniaxial compression of polycrystalline targets using femtosecond X-ray diffraction
Author(s) -
David McGonegle,
Andrew Higginbotham,
E. Galtier,
E. E. McBride,
M. I. McMahon,
Despina Milathianaki,
Hae Ja Lee,
Bob Nagler,
S. M. Vinko,
J. S. Wark
Publication year - 2014
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/500/11/112063
Subject(s) - crystallite , femtosecond , materials science , diffraction , compression (physics) , x ray crystallography , crystallography , optics , composite material , physics , chemistry , laser , metallurgy
Although the pressures achievable in laser experiments continue to increase, the mechanisms underlying how solids deform at high strain rates are still not well understood. In particular, at higher pressures, the assumption that the difference between the longitudinal and transverse strains in a sample remains small becomes increasingly invalid. In recent years, there has been an increasing interest in simulating compression experiments on a granular level. In situ X-ray diffraction, where a target is probed with X-rays while a shock is propagating through it, is an excellent tool to test these simulations. We present data from the first long-pulse laser experiment at the MEC instrument of LCLS, the world's first hard X-ray Free Electron Laser, demonstrating large strain anisotropies. From this we infer shear stresses in polycrystalline copper of up to 1.75 GPa at a shock pressure of 32 GPa. © Published under licence by IOP Publishing Ltd