零件表面钝化处理对杜瓦放气率的影响

Effect of part surface passivation on Dewar outgassing rate

红外焦平面探测器杜瓦组件的真空绝热空间内存在多种气体来源,其中最大的气体来源是材料放气。文中针对制冷型红外焦平面探测器杜瓦组件真空绝热空间内表面吸附气体的解析、体扩散、渗透放气污染问题影响制冷启动时间,限制红外探测器组件的使用寿命,设计了一种用于红外探测器杜瓦内表面钝化处理方案,基于某型杜瓦产品实现了杜瓦内壁钝化膜的制备。采用压强上升法进行放气率对比测试,并通过四极质谱仪进行了气体成分分析。放气率测试试验结果表明,钝化膜有效抑制了氢气的释放,杜瓦放气率降低一半以上。杜瓦内表面钝化膜处理方法简单有效,提升了真空寿命,具备工程化推广价值。

There are many gas sources in the Dewar’s vacuum insulation space,the biggest gas source is material outgassing.The problem of outgassing pollution caused by the desorption,volume diffusion,and penetration of the adsorbed gas on the inner surface of the vacuum insulated space of the refrigerated infrared focal plane detector Dewar component was focused,which affected the cool down time and restricted the service life of the infrared detector component.A passivation treatment plan for the inner surface of the infrared detector Dewar was designed,and the passivation film on the inner wall of the Dewar was prepared based on a certain type of Dewar product.The pressure rise method was used to compare the outgassing rate,and the gas composition was analyzed by a quadrupole mass spectrometer.The test results of outgassing rate show that the passivation film effectively inhibits the release of hydrogen,and the outgassing rate of Dewar is reduced by more than half.The processing method of the passivation film on the inner surface of the Dewar is simple and effective,which improves the vacuum life and has engineering promotion value.