Real-time characterization of dislocation slip and twinning of shock-compressed molybdenum single crystals

Characterizing the fundamental micromechanisms activated during plastic deformation is critical to explain the macroscopic shock response of materials and develop accurate material models. In this paper, we investigate the orientation dependence, and the mediated slip and twin systems on $[1\phantom{\rule{0.16em}{0ex}}0\phantom{\rule{0.16em}{0ex}}0]$ and $[1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}1]$ bcc molybdenum single crystals shock compressed up to 18 GPa with real-time Laue x-ray diffraction measurements. We report that dislocation slip along the ${1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}0}\ensuremath{\langle}1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}1\ensuremath{\rangle}$ and ${1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}2}\ensuremath{\langle}1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}1\ensuremath{\rangle}$ systems is the governing deformation mechanism during compression with negligible anisotropy observed at the Hugoniot state. We provide real-time evidence that molybdenum undergoes deformation twinning along ${1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}\overline{\phantom{b}2}}\ensuremath{\langle}1\phantom{\rule{0.16em}{0ex}}1\phantom{\rule{0.16em}{0ex}}1\ensuremath{\rangle}$ during shock release.