充气塑料柱腔的制备与保气半寿命

Fabrication and half-life time of gas-filled plastic hohlraum

研究了聚苯乙烯塑料柱腔的两种制备方法：采用聚苯乙烯溶液旋转涂层和熔体浸涂。聚苯乙烯熔融后浸涂制备的塑料柱腔存在一定的结晶取向和很多气泡,去掉铜芯轴后,塑料柱腔因缺陷太多几乎不能保气,成品率非常低,不到10%。利用聚苯乙烯溶液通过多次旋转涂层和烘干过程制备的塑料柱腔具有很低的表面粗糙度,柱腔厚度为10~30 m,表面粗糙度5~20 nm,采用0.3~0.4μm聚酰亚胺膜封口保气,气体介质为氪气,通过X射线荧光谱仪测量柱腔保气半寿命约24 h。采用保气罐储存和运输无源塑料柱腔充气靶,打靶时腔内气体密度可保持在初始状态的92%左右。

This paper focuses on the fabrication and half-life time of the gas-filled polystyrene hohlraum.There are two ways to fabricate the polystyrene hohlraum,i.e.spin coating with polystyrene solution and dip coating with molten polystyrene.Experiments show that many bubbles and orientation crystallization exist in the plastic hohlraum made by polystyrene melt,and the hohlraum can hardly retain gas due to too many cracks in it after the removal of copper mandrels.Plastic hohlraums made by spin coating,10 to 30 μm in thickness and 5 to 20 nm in surface finish,are sealed with 0.3~0.4 μm thick polyimide films.The half-life time of these hohlraums filled with kropton gas is more than 24 h measured by X-ray fluorescence spectrometry.Held in a gas container,the gas can keep about 92% of the initial density inside the target just before shotting.