Thermal conductivity and mechanical properties of graphite/Mg composite with a super-nano CaCO3 interfacial layer

Li Zhang; Kun-Kun Deng; Kai-Bo Nie; Cui-Ju Wang; Chao Xu; Quan-Xin Shi; Yu Liu; Jie Wang

doi:10.1016/j.isci.2023.106505

Thermal conductivity and mechanical properties of graphite/Mg composite with a super-nano CaCO₃ interfacial layer

iScience. 2023 Mar 28;26(4):106505. doi: 10.1016/j.isci.2023.106505. eCollection 2023 Apr 21.

Authors

Li Zhang^{1

2}, Kun-Kun Deng¹, Kai-Bo Nie¹, Cui-Ju Wang¹, Chao Xu³, Quan-Xin Shi¹, Yu Liu¹, Jie Wang⁴

Affiliations

¹ Shanxi Key Laboratory of Advanced Magnesium-based Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
² Teaching Center of Experiment and Practice, Shanxi Datong University, Datong 037000, China.
³ School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
⁴ National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240, China.

Abstract

Incorporating graphite/graphene into a Mg alloy matrix is a promising approach for developing lightweight heat dissipation materials. However, carbon material is inherently incompatible with Mg because of their distinctly different surface characteristics, resulting in the challenge of composite fabricating and interface controlling. Herein, a new strategy of in situ interfacial modification was proposed to achieve excellent thermal conductivity and mechanical properties in graphite/Mg composites. A super-nano CaCO₃ interfacial layer was reported in this paper. The detailed interfacial structure, reaction thermodynamics and kinetics, and interface strengthening mechanisms were analyzed and discussed. Several preferential epitaxial relationships of the Mg/CaCO₃ interface were revealed, which are conducive to minimize the interfacial energy, stabilize and strengthen the interface. Moreover, strong ionic bond of graphite/CaCO₃ interface was demonstrated. The strong chemical interface bonding of graphite-Mg via in situ interface modification facilitates both the interfacial cohesion and interfacial thermal conduction, which endows the graphite/Mg composites with superior strength-thermal conductivity synergy.

Keywords: Materials science; Mechanical property.