Journal Article

Light emission properties of sapphire under shock loading in the stress range of 40a120 GPa

Zhang, NingChao, Zhang, MingJian, Chen, JunXiang, Peng, XiaoJuan, Liu, FuSheng

2013

Overview

The measurement of emissions from the window material of sapphire was performed through multi-wavelength pyrometer and spontaneous spectroscopic techniques in the pressure range of 40a120 GPa. The results showed that the spectral distribution with wavelength clearly fit well with the grey-body spectrum. We have analyzed the emissions and discovered they mostly came from the shear banding, which is a typical thermal radiation. The radiance intensity changing linearly with time revealed it was a volume effect. All of the data from pyrometer can be explained by the model of Bosloughas study, especially for pressures over megabar. The color temperature of shocked sapphire changing with increased stress disagrees with the computed melt curve which is likely explained by the different phase structures of sapphire.