基于朗缪尔吸附模型的杜瓦真空寿命评估研究

影响杜瓦真空寿命的主要是内部材料出气。针对红外探测器杜瓦的出气机理及密封前需长时间排气特点，提出了以满足朗缪尔吸附模型的脱附速率方程作为杜瓦出气率模型的真空寿命评估方法。创新性地提出排气结束时变温监测离子流的方法，获得同覆盖度下不同温度的出气率，消除覆盖度的影响，提取了杜瓦的整体出气激活能，推导出存储温度下初始出气率及出气率随时间变化的关系。实验发现三个杜瓦在不同测试条件下获得的激活能差异为8.8%。跟踪封装2年的杜瓦热负载，验证估算的寿命误差为7.2%。本研究为小批量、多样化杜瓦提供了便利的真空寿命无损检测评估方法。

A Dewar vacuum lifetime estimate based on Langmuir adsorption model

The main factor affecting the vacuum life of the infrared detector Dewar is the internal material outgassing. The Langmuir adsorption model outgassing equation is used to calculate the vacuum lifetime due to the outgassing mechanism and the long-term degassing procedure of the Dewar. An innovative method of changing the temperature at the end of the degassing procedure was proposed to obtain the outgassing activation energy. The outgassing rate was measured at different temperatures while simultaneously removing the influence of coverage on the outgassing rate. The outgassing rates at storage temperature and the rule of outgassing rate changing over time were deduced. The difference among the three Dewar outgassing activation energies obtained in different conditions was 8.8%. The heat load of the Dewar was tracked for two years to verify the method. The estimated error of Dewar''s vacuum lifetime was 7.2%. It is a non-destructive testing estimation method for the vacuum life of small and diverse Dewar.