Reanalysis of the shock temperatures for iron employing the method of Tan and Ahrens permits reinterpretation of previously reported Fe-Al2O3, and Fe-LiF interface radiance temperatures. The reduced data for iron foils and films in contact with Al2O3, and LiF windows are consistent and indicate that the melting temperatures for iron range from 5300 K at 120 GPa to 7300 K at 240 GPa. This revised analysis indicates that the melting temperatures are ~ 350 K higher than previously reported on the basis of a simpler analysis. Data for the initial density of a series of iron foils indicate a density of 7.87 ± 0.17 g/ m3, which indicates a total absence of porosity. Scanning electron microscope images of the 0.3 to 0.4 μm thick iron foils used in the experiments indicate no detectable initial porosity. However these films demonstrate a variation in thickness of ~0.1 μm which induces thermal transients at the iron-window interfaces with durations of ~ 4 x 10-11 s. These temperature fluctuations would occur more rapidly than the 10-9 s time resolution of present recording methods.
ASJC Scopus subject areas
- Condensed Matter Physics