复材结构航天器静电特性及防护技术

Electrostatic characteristics and protection technology of composite material structure in spacecraft

复合材料结构航天器静电防护特性相对于金属材料结构航天器而言呈现出较大差异。文章针对新型天地往返无人航天器,研制了高温条件下材料电阻率测试专用探头和测试系统,并从材料静电特性、静电防护设计等方面开展了复材结构航天器静电特性研究。结果表明:作为冷结构的碳纤维复合材料属于导静电型材料,可以满足防静电需要;在航天器地面着陆后,可通过导静电轮胎将飞行器冷结构上的静电释放至大地,实现对航天器着陆后的静电防护;采用局部静电消除的方法,可消除热防护绝缘材料上的静电,将航天器热防护材料表面静电降低至安全范围内,保证再入返回着陆后人员的操作安全。

For the new type unmanned space shuttle,it is essential to use composite structural materials.The electrostatic protection characteristics of the composite structure in spacecraft differs greatly from those of the traditional metallic spacecraft structure.In this paper,such characteristics are studied from the aspects of the electrostatic characteristics of materials and the electrostatic protection design.It is shown that the bearing structure made of carbon fiber composite,a kind of electrostatic conductive material,can meet the antistatic requirement.After the spacecraft is landed on the ground,the accumulated static charges on the surface of its bearing structure can be released to the Earth by the electrostatic conductive tires,to realize the electrostatic protection of the spacecraft.By using the method of the local electrostatic discharge,the static charges on the thermal protective insulating materials can be eliminated,and the electrostatic level of the surface of the thermal protective system can be reduced to a safe level to ensure the operation safety for the ground personnel.