航天器表面材料二次电子发射特性研究

Study on Characteristics of Secondary Electron Emission for Spacecraft Surface Materials

摘要: 航天器在轨表面入射离子、电子产生的二次发射电子流随二次电子发射系数的变化而变化,通过建模仿真对二次电子发射系数对充电电流、充电电位的影响进行验证。通过对航天器用表面材料ITO(Indium tin oxide,氧化铟锡)膜二次发射电子系数测试,测试结果与标准参数基本一致;测试结果表明,二次电子发射系数与材料厚度相关,且随着材料厚度的增加二次电子发射系数减小,因此可以通过改变航天器表面材料厚度的方式影响表面材料的二次电子发射系数,从而控制航天器表面材料的带电状态。

Abstract: The secondary emission electron flow generated by the incident ions and electrons on the spacecraft surface changes with the change of the secondary electron emission coefficient.The influence of the secondary electron emission coefficient on the charging current and potential is verified by modeling and simulation.The surface material ITO (Indium tin oxide) used in spacecraft was studied.The results show that the secondary electron emission coefficient is related to the thickness of the material,and decreases with the increase of the material thickness.Therefore,the secondary electron emission coefficient can be affected by changing the thickness of the spacecraft surface material Controlling the charged state of spacecraft surface materials.