碳基高导热材料及其在航天器上的应用  

Carbon materials with high thermal conductivity and its application in spacecraft

作　　者：童叶龙[1,2] 陶则超 李一凡[1,2] 刘占军[3] 江利锋 殷亚州[1,2] TONG Yelong;TAO Zechao;LI Yifan;LIU Zhanjun;JIANG Lifeng;YIN Yazhou(Beijing Institute of Spacecraft System Engineering,Beijing 100094,China;Beijing Key Laboratory of Space Thermal Control Technology,Beijing 100094,China;Insititute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China)

机构地区：[1]北京空间飞行器总体设计部,北京100094 [2]空间热控技术北京市重点实验室,北京100094 [3]中国科学院山西煤炭化学研究所,太原030001

出　　处：《中国空间科学技术》2022年第1期131-138,共8页Chinese Space Science and Technology

基　　金：国家自然科学基金(11973100)。

摘　　要：在分析航天器对于高导热材料的需求及应用特点的基础上,将碳基导热材料分为高导热石墨扩热板和高导热柔性石墨膜,总结了其在航天器上的典型应用场景。高导热柔性石墨膜可用于复杂结构等温化设计、柔性热传输等,高导热石墨扩热板可用于大功率元器件或设备扩热与传输。针对现有柔性导热材料柔韧性差、尺寸小、厚度薄等应用瓶颈,采用固相发泡技术制备石墨气泡,再通过机械辊压将其压制成表面含“褶皱”的石墨膜,利用热塑性加工技术,研制了热导率优于750 W/(m·K)的亚毫米级厚的高导热柔性石墨膜,将抗拉强度由6 MPa提高至20 MPa,厚度由几十微米提高至亚毫米级,同时使其尺寸可延展,将其应用于航天器大型载荷安装结构,温度梯度由8.9℃减小到2.5℃,可有效提高航天器低热导率结构件的等效热导率;采用高温热压技术制备高导热石墨基材,并通过磁控溅射的方式在石墨表面完整沉积金属镀层,解决了表面掉黑的问题,成功应用于某卫星固态存储器大功率器件散热。The requirement and typical application of graphite materials with high thermal conductivity in spacecraft were summarized.High thermal conductivity flexible graphite film can be used to improve the thermal conductivity of the complex or as a flexible thermal strap.Thermal louvers can be used for heat dissipation of high-power components or electronics.Aiming at the application bottlenecks of existing flexible thermal conductive materials such as poor flexibility,small size,and thin thickness,a new type of flexible graphite film with high thermal conductivity was promoted and developed.Graphitic films with wrinkles at surfaces were prepared by mechanical rolling using graphitic bubble as precursor which derived according to“solid foaming”method.Subsequently,millimeter-level thick tape with thermal conductivity above 750 W/(m·K)were fabricated based on thermoplastic processing.Furthermore,the tensile strength of this thermal conductive tape was elevated from 6 MPa to 20 MPa while the dimension can be extended under mechanical stress.Applying the flexible graphite film to the large-scale load installation structure of the spacecraft,the temperature gradient is reduced from 8.9°C to 2.5°C,which can effectively improve the equivalent thermal conductivity of the spacecraft's low thermal conductivity structure.High thermal conductive graphitic blocks were prepared by hot-pressing method.Then graphite products as thermal louvers were completely coated with metal layer in order to prevent the graphite particle at surface from peeling off,which was successfully applied to heat dissipation of a high-power solid-state memory device for satellite.

关 键 词：航天器 热控制 扩热板 石墨材料 温度梯度 热导率 

分 类 号：V45[一般工业技术—材料科学与工程]