添加铜网对片层石墨/Al基复合材料热物理性能的影响

来源：中国复合材料学会

《复合材料学报》优先在线发表论文。

摘  要：使用盐浴法对片层石墨(GFs)进行表面镀Si处理，采用真空热压法制备片层石墨/Al基复合材料(Si-GFs/Al)。向Si-GFs/Al基复合材料中添加10vol%的铜网，研究了铜网对Si-GFs/Al基复合材料热导率和力学性能的影响。使用扫描电子显微镜(SEM)、聚焦离子束(FIB)和透射电子显微镜(TEM)对Si-GFs/Al基复合材料的微观结构和微观界面进行表征，并分析了复合材料的断裂机制。结果表明，添加铜网使Si-GFs/Al基复合材料内部出现了高聚集定向GFs带，形成高导热通道。当GFs 体积分数为30%~40%时，Si-GFs/Al基复合材料的热导率提升了约20%，弯曲强度提升了40%以上。当GFs 体积分数为40%时，Si-GFs/Al基复合材料热导率和弯曲强度同时达到一个优值，分别为512W/(m·K)和127MPa。

关键词：石墨/Al复合材料；热导率；弯曲强度；真空热压法；界面反应

Abstract: The surface of graphite flakes(GFs) was coated with Si by salt bath method, and the graphite flakes/Al matrix composites (Si-GFs/Al) were prepared by vacuum hot pressing method. 10vol% Cu mesh was added to Si-GFs /Al matrix composites, and the effects on thermal conductivity and mechanical properties were studied. The microstructure and micro interface of Si-GFs /Al matrix composites were characterized by scanning electron microscopy (SEM), focusing ion beam (FIB) and transmission electron microscopy (TEM). The fracture mechanism of the composites was analyzed. The results show that highly clustered GFs bands have been built in the Si-GFs /Al matrix composites after Cu mesh added. When the GFs volume fraction is 30%~40%, the thermal conductivity of Si-GFs /Al matrix composites increases by about 20%, and the bending strength increases by more than 40%. The thermal conductivity and bending strength of Si-GFs /Al matrix composites with 40vol% GFs both reaches a satisfactory value, which are 512(W/m·K) and 127MPa, respectively.

Keywords: graphite/Al composites; thermal conductivity; bending strength; hot pressing method; interface analysis

作者：曾凡坤等，江汉大学 机电与建筑工程学院，武汉

通讯作者：薛晨等，中国科学院宁波材料技术与工程研究所，宁波

全文详见中国知网学术期刊优先数字出版。