Sound speed measurements in lithium fluoride single crystals shock compressed to 168 GPa along [100]
The shock wave response of [100] lithium fluoride (LiF) single crystals at high stresses is of long-standing interest due to their extensive use as optical windows in dynamic compression experiments. The report of melting in shock compressed LiF single crystals between 134 GPa and 152 GPa – based on a single sound speed datum [J. Appl. Phys. 117, 045901 (2015)] – was surprising because good optical transmission was previously demonstrated in LiF shock compressed to ~200 GPa [J. Appl. Phys. 116, 033515 (2014)]. To address these apparent differences, we report on plate impact experiments on [100] LiF single crystals shock compressed to 168 GPa. Wave profiles were measured using laser interferometry to determine Hugoniot states and longitudinal sound speeds in shock compressed LiF. The measured Hugoniot states are in good agreement with those measured in previous studies. However, the measured sound speeds presented here show no evidence of melting up to 168 GPa. In particular, the abrupt drop reported previously in sound speed at 152 GPa was not observed in the present work. Furthermore, our results establish a lower bound of 168 GPa for the onset of melting in shock compressed LiF single crystals.
- Research Organization:
- Washington State Univ., Pullman, WA (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA), Office of Defense Programs (DP)
- Grant/Contract Number:
- NA0003957
- OSTI ID:
- 1818134
- Journal Information:
- Journal of Applied Physics, Vol. 130, Issue 3; ISSN 0021-8979
- Publisher:
- American Institute of Physics (AIP)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Shock-induced melting of [100] lithium fluoride: Sound speed and Hugoniot measurements to 230 GPa
Elastic-plastic deformation of molybdenum single crystals shocked to 12.5 GPa: Crystal anisotropy effects