氟化锂和蓝宝石单晶冲击消光及其对辐射测温的影响  

Shock-induced optical extinction in LiF and sapphire crystals and its significance in the radiant temperature determination

作　　者：周显明[1,2] 操秀霞[1,2] 李俊[1] 李加波[1] 卢铁城[2] 

机构地区：[1]中国工程物理研究院流体物理研究所冲击波物理与爆轰物理重点实验室,绵阳621900 [2]四川大学物理科学与技术学院,成都610065

出　　处：《原子与分子物理学报》2012年第3期481-487,共7页Journal of Atomic and Molecular Physics

基　　金：中国工程物理研究院科学技术发展基金(2008B0101001)

摘　　要：采用冲击波压缩原位光源技术结合时间分辨多波长高温计测量,研究了氟化锂和蓝宝石单晶样品的冲击消光现象,实验压力范围50～183了GPa,中心波长覆盖254～800 nm.结果表明,氟化锂单晶样品在实验压力下透过率变化不大,对界面温度的拟合值影响不明显,只是使表现发射率略有下降;当压力低于90GPa时,蓝宝石的消光情况同氟化锂接近,对界面温度的拟合影响也不明显;而当压力高于99 GPa时,蓝宝石呈现明显的消光衰减现象,实验测定的消光系数随压力增加而增加,与波长间呈反比关系,与文献报道250 GPa高压消光特性一致.研究还发现,蓝宝石窗高压消光行为对界面温度的测量存在较大的影响,使得拟合温度明显偏低.本文研究对发展非透明材料冲击测温技术具有一定的参考价值.Shock-induced optical extinction in LiF and sapphire single crystals had been studied using a time-resolved multi-wavelength pyrometry measurements incorporated with a dynamically generated in- situ light source. Shock pressure in the samples covers a 50~183 GPa range and the central wavelength in the pyrometer ranges from 254 nm to 800 nm. Our results demonstrate that the measured transmit- tance in the LiF samples under investigation varies little which has a negligible influence on the fitted in- terfaciaI temperature with an apparent emissivity decreased a little. When the pressure in the sapphire sample is less than 90 GPa, the fitted results show similar behavior as it does in the LiF window. As the shock pressure is over 99 GPa, the sapphire samples show remarkable extinction decay of light radia- tion. The measured optical extinction coefficient increases with the increasing pressure, and decreases with the wavelength, which is in consistent with the 255 GPa high-pressure results in the literature. We also find that the optical extinction behavior in shocked sapphire under high-pressures has an essential influence on the interracial temperature measurements, and resulted in a lower fitted temperature The.present study may have some reference value for developing technique of shock temperature measure- ment for opaque materials.

关 键 词：氟化锂 蓝宝石 冲击消光 冲击温度 

分 类 号：O432.1[机械工程—光学工程]