Influence of carbon source type on microstructure and properties of in-situ graphene/Cu composites

In the realm of advanced materials research, graphene/Cu composites have emerged as promising candidates due to their exceptional properties. This study explores the critical role of carbon source type in optimizing the performance of in-situ graphene/Cu composites. By systematically investigating 18-carbon chain olefins with different end-functional groups in octadecene (ODE), oleic acid (OA) and oleamine (OAM) as carbon sources, we uncover their profound impact on graphene quality, composite grain boundaries, and load transfer efficiency. OA and OAM can enhance carbon retention and promote the formation of Cu2O and Cu3N nanoparticles, thereby enhancing the binding of graphene/Cu interfaces and improving load transfer. Moreover, the functional groups in the carbon sources play a crucial role in copper grain refinement and strengthening, which enhances the overall mechanical properties. Specially, the composites prepared with OAM demonstrated superior mechanical properties, including the highest yield strength (468 MPa), tensile strength (515 MPa), and fracture elongation (11.9 %), as well as good electrical conductivity (87.8 % IACS) and a low resistance temperature coefficient (3.46 x 10-3 degrees C- 1). This study underscores the importance of carbon source selection in optimizing graphene/Cu composites and provides valuable insights into the intricate relationship between chemistry, microstructure, and material properties, paving the way for the rational design of multifunctional materials.