冲击压缩LY12铝向不同充气介质卸载后的光反射率实验研究

Experimental study of light reflectivity of the shocked LY12 aluminum unloading to different gases

用二级氢气炮作为冲击压缩加载工具和多通道瞬态辐射高温计作为主要测量系统,对装有初始压力为6 MPa和1.2 MPa的氦气、氘气和氢氘混合气体冲击压缩等离子体的光谱幅亮度历史进行了测量.根据实测记录信号波形的有关特征量,拟合得到了冲击压缩LY12铝基板表面光反射率R.结果发现:受冲击LY12铝基板表面对340～800nm波长向不同充气介质氦气、氘气和氢氘混合气体等离子体卸载后的光反射率为约0.4,为静态下铝基板反射率(约0.8)的一半.并对动态加载下反射率降低的机理进行了探讨.

Spectral radiance histories of plasma for He, D2 and H2+D2 gas mixtures with the initial pressure p0 = 0.6, 1.2 MPa after shock compressed by a two-stage light-gas gun was measured by using transient radiation pyrometer. According to the signal amplitude of spectral radiance history, the light reflectivity R of LY12 aluminum base-plate surface after shocked was obtained from a typical record by means of fit. It was found that the R (wavelength ranges 340-800 nm) of shocked LY12 aluminum base-plate surface unloading to He, D2 and H2+D2 mixing gas plasma is about 0.4, which decreases to half of the static state reflectivity (-0.8). The reason of reflectivity decrease at dynamic loading is discussed.