In the trend of integration of structure and function, novel thermal management materials are urgent to be developed owning good mechanical properties as well as excellent thermal properties. In this work, a complete and dense copper (Cu) coating with a thickness of 400 nm was deposited on the surfaces of graphite films (GFs) by ultrasonic-assisted electroless plating, which can improve the surface roughness of GFs and interfacial bonding between GFs and Cu foils. Cu-coated and uncoated GFs reinforced copper matrix laminated composites (noted as GFs(Cu)/Cu and GFs/Cu) were fabricated by optimized vacuum hot-pressing sintering. Based on the scratch test and microstructures of GFs(Cu) and GFs(Cu)/Cu composites, addition of Cu coating can improve the interfacial adhesion and element diffusion behavior, and intuitively explains the mechanical interlocking effect at the C–Cu interface. On basis of the nanoindentation mechanical properties across GFs(Cu)/Cu and GFs/Cu interfaces, the interfacial transition region with Cu coating of ~3 μm is three times of that without Cu coating. Flexural strength of 27.6 vol% GFs(Cu)/Cu laminated composite is 45.9 MPa, which is 56% higher than that of the corresponding GFs/Cu laminated composite. In-plane thermal conductivity (TC) and out-of-plane coefficient of thermal expansion (CTE) of 69.4 vol % GFs(Cu)/Cu laminated composite are 1177.8 W/m·K and −2.5 ppm/K respectively, which could be explained on the theoretical calculations and interfacial structures. In conclusion, the Cu coating on surfaces of GFs can generally improve the interfacial bonding, mechanical properties and thermal properties of GFs(Cu)/Cu laminated composites. It provides an effective way to develop novel structural and functional materials for thermal management.

在结构与功能一体化的趋势下，迫切需要开发具有良好机械性能和优异热性能的新型热管理材料。在这项工作中，通过超声辅助化学镀在石墨膜（GFs）表面沉积了一层完整致密的铜（Cu）涂层，厚度为 400 nm，可以改善 GFs 的表面粗糙度和 GFs 之间的界面结合和铜箔。通过优化真空热压烧结制备了镀铜和未镀铜的 GFs 增强铜基层压复合材料（记为 GFs(Cu)/Cu 和 GFs/Cu）。基于GFs(Cu)和GFs(Cu)/Cu复合材料的划痕测试和微观结构，添加Cu涂层可以改善界面粘附和元素扩散行为，直观地解释了 C-Cu 界面的机械互锁效应。基于 GFs(Cu)/Cu 和 GFs/Cu 界面的纳米压痕力学性能，具有~3 μm 铜涂层的界面过渡区域是没有铜涂层的界面过渡区域的三倍。27.6 vol% GFs(Cu)/Cu叠层复合材料的抗弯强度为45.9 MPa，比相应的GFs/Cu叠层复合材料高56%。69.4 vol % GFs(Cu)/Cu层状复合材料的面内热导率(TC)和面外热膨胀系数(CTE)分别为1177.8 W/m·K和-2.5 ppm/K,解释理论计算和界面结构。总之，GFs表面的Cu涂层通常可以改善界面结合，GFs(Cu)/Cu层状复合材料的力学性能和热性能。它为开发用于热管理的新型结构和功能材料提供了一种有效的方法。