本文介绍了一种用于激光状态方程实验冲击波延时的密度梯度气凝胶飞片靶的制备及表征方法。以间苯二酚和甲醛为原料,去离子水为溶剂,碳酸钠为催化剂,在溶胶-凝胶工艺的基础上采用逐层凝胶和微模具成型工艺,经过脱模、乙醇替换和真空干燥,制备了4层密度梯度渐变间苯二酚-甲醛(RF)有机气凝胶飞片靶,并使用傅里叶红外光谱仪、扫描电子显微镜、X射线相衬成像仪和比表面积及孔隙分析仪对飞片靶的成分、形貌、密度、层间界面耦合情况及微观结构进行表征。实现了总体厚度约120μm、单层厚度一致、各层均匀性良好且密度变化范围约400~1 200mg/cm3的4层密度梯度RF气凝胶飞片靶的制备和表征。
The method about fabrication and characterization of graded density aerogel flyer target for extending loading time in laser-driven equation of state(EOS) experiment was introduced.The preparation of the target involved the synthesis of organic resorcinol-formaldehyde(RF) aerogel.RF hydrosol was prepared via sol-gel process with resorcinol-formaldehyde-water system and catalyzed by sodium carbonate.Also,an airtight micro-mold was used in layer-by-layer gelation process.After gelation,the RF wet gel was demoulded in ethanol condition and substituted with ethanol one time per day for three days to remove the residual solution.The treated RF wet gel was converted to RF aerogel via vacuum drying after the residual solution was completely removed.The Fourier transform infrared spectroscopy,field emission scanning electron microscopy(FESEM),X-ray phase contrast imaging instrument and surface area and porosity analyzer were used to characterize the composition,morphology,density,interlayer coupling and microstructure of the flyer target.A four-layer target with total thickness of about 120 μm and density of about 400-1 200 mg/cm3 was obtained and characterized in the experiment.