Abstract
A new geometry of X-ray diffraction survey of single crystal sample in
the monochromatic X-ray radiation was developed and applied to obtain a
diffraction patterns of shock-compressed NaCl single crystals. This
diffraction patterns contain the reflections of different crystal planes
and allows to derive both the longitudinal and the transversal strain
from the horizontal and vertical shift of the reflections. Compression
of the 5-mm [100]-oriented single crystals backed with 0.5-mm graphite
window was produced by 6-mm steel impactors accelerated up to velocity
200 - 500 m/sec in 25-mm pneumatic gun. The 30-nsec pulse X-ray source
(based on Scandiflash 300 X-ray pulse system) was triggered at the
different instances after arrival of the shock wave at the NaCl-window
interface. The velocity of the free surface of the graphite window was
continuosly monitored by velocity interferometer (VISAR (Barker, L.M.,
Hollenbach, R.E., J. Appl.Phys, 1974, 45, p.4872-4887)). In the impact
experiments performed with the different impact velocities and with the
triggering of the X-ray flash at the time instances corresponding to the
different states of the NaCl at the plastic wave front no evident
transversal strain were found. The material seems to be able to maintain
the state of 1-D strain under intensive plastic deformation.
Original language | English |
---|---|
Title of host publication | American Physical Society, Shock Compression Meeting 1997 |
State | Published - 1 Jul 1997 |