薄膜材料气体微量渗透率动态流量测试方法研究

Study on Measurement Method of Micropermeability for Thin-film Materials

固体材料的气体渗透是材料的固有特性,是影响密闭容器密封性能的原因之一,在某些场合材料的气体渗透已经成为导致产品压力降低和真空失效的主要因素。介绍了一种采用热阴极电离规和四极质谱计作为核心测量传感器,实现渗透低压侧总压力和分压力精确测量,并结合固定流导法实现渗透低压侧漏放气速率测量,再依据渗透机理获得薄膜材料气体微量渗透率。对利用上述原理研制的薄膜材料新型气体微量渗透率测量装置开展了典型薄膜材料渗透性能测试,结果表明,所研制装置的渗透系数测量下限小于1×10^-14 m^2/s,测得真空绝热板(Vacuum Insulation Panel,VIP)行业用典型高阻隔薄膜对H 2O和N 2的渗透率在10^-2 g/(m^2·d)量级,与国外资料给出的VIP材料渗透率10-2~10^-3 g/(m^2·d)范围相当。

The gas permeation is one of inherent characteristics of solid materials and one of reasons effecting sealing performances of closed containers.The gas permeation of materials is one of main factors which lead to the pressure decay and vacuum loss in some containers.For example,the research tasks of near-space stratosphere airship and long-life spacecraft have put forward more strict requirements than before about the performances of lifetime,reliability and safety.The vacuum insulation product and vacuum electronic device need to obtain and maintain vacuum for a long time.A kind of measurement method of gas permeation rate is studied.In this method,the quadrupole mass spectrometer and hot cathode ionization gauge are used as the key measurement sensors,and the constant conductance method is used to measure the leakage and outgassing rate on the low pressure side of permeability sample.Based on the above principle,a new measuring device of micro-permeability for thin-film materials is developed.And the device performance and a type thin-film material are carried out.The experimental results show that the lower limit of micro-permeability is less than 1×10^-14 m^2/s,the H 2O and N 2 permeation quantity of typical high separation membrane for VIP(Vacuum Insulation Panel)industry are on the order of 10^-2 g/(m^2·d).