Peak states of molybdenum single crystals shock compressed to high stresses

Abstract

To determine crystal anisotropy effects at high stresses, peak states behind the plastic shock waves were examined in BCC single crystals. Using plate impact experiments, molybdenum (Mo) single crystals were shock compressed up to 190 GPa elastic impact stress along [100], [110], and [111] orientations. Laser interferometry was used to measure wave velocities and particle velocity profiles at the Mo-LiF window interface. These data were analyzed to obtain in-material quantities in the peak states. The Hugoniots for [100] and [110] orientations were comparable, but the Hugoniot for the [111] orientation was different from the other two orientations. Also, these Mo single crystal Hugoniots display differences from the polycrystalline Mo Hugoniots. Although none of the differences can be considered large, the present results demonstrate that, unlike FCC metal single crystals (Cu, Al), some anisotropy is preserved in Mo single crystal Hugoniots even at high stresses.

Predicting shock hugoniot and equation of state of single-crystal molybdenum by molecular dynamics simulation

“…Both the hugoniot obtained in NEMD simulation show good agreement with experimental data [6,7] pertaining to polycrystalline sample. Available single-crystal data for [001] direction [8] is also shown. This establishes the validity of the chosen interatomic potential for the present requirement in high-pressure applications.…”