Superior Thermal Conductivity of Graphene Film/Cu-Zr Alloy Composites for Thermal Management Applications
Guo Chang, Lühua Wang, Yongjian Zhang, Xiang Li, Kaiyun Chen, Dongxiao Kan, Wei Zhang, Shuang Zhang, Longlong Dong, Liang Li, Xue Bai, Hailong Zhang, Wangtu Huo
Abstract
As the power density of electronic devices continuously increases, there is a growing demand to improve the heat conduction performance of thermal management materials for addressing heat dissipation issues. Single-/few-layer graphene is a promising candidate as a filler of a metal matrix due to its extremely high thermal conductivity (k); however, the well-arranged assembly of 2D-component graphene with a high volume fraction remains challenging. Herein, we integrated a novel graphene-based macroscopic material of graphene film (GF) into a Cu matrix by infiltrating molten Zr-microalloyed Cu into a spirally folded and upright-standing GFs skeleton. The microstructure of the GF/Cu composites was regulated by an interface modification strategy. The GF/Cu composites with a spirally layered microstructure exhibit a superior k of 820 W/m K in the axial direction, much higher than that of Cu-matrix composites reinforced with graphene nanosheets (generally <500 W/m K) and twice that of Cu. The thermal transfer mechanisms were investigated by experiments and theoretical calculations. The results reveal that the excellent performance is attributed to the construction of high-heat conduction channels and a positive coordinating effect at the Zr-modified GF/Cu interface. Meanwhile, the relation between interfacial microstructure and heat transfer is established in the composites using interfacial thermal resistance as a bridge. This work yields in-depth insight into the heat conduction mechanism in highly oriented structures and provides a promising solution for the thermal management issues of high-power electronics.