# Advancing Copper Wire Technology: Graphene/Cu Composites for Superior Conductivity and Strength
## 4 Conclusions  
The structural and performance investigation of Gr/Cu composite copper powders, comprising varying shapes (dendritic and spherical) and graphene contents, yields substantial insights into the role of graphene in enhancing copper composites. The study confirms that both dendritic Gr/Cu-Z and spherical Gr/Cu-T contained high-quality graphene with minimal defects. Notably, the dendritic Gr/Cu-Z had less graphene, featuring 1-2 layers, whereas the spherical Gr/Cu-T contained approximately 5 layers of graphene. This variation in graphene content significantly influenced the structural characteristics and performance of the composites. The integration of graphene, particularly during the annealing process, effectively inhibited grain growth, leading to smaller grain sizes and a greater number of grain boundaries. This structural modification through grain refinement and effective load transfer via graphene notably enhanced the mechanical prop  
Figure 10: SEM morphology of the fracture surface of annealed composite wire: (**a–c**) pure Cu, (**d–f**) Gr/Cu-Z and (**g–i**) Gr/Cu-T composite wires.  
erties of the composites. Additionally, the introduction of high-quality graphene facilitated rapid electron transport and reduced grain dislocation density, which decreased electron scattering and subsequently enhanced electrical conductivity. The performance metrics were impressive, with annealed composite wires achieving conductivity levels of 100% IACS and above, along with tensile strengths of 238 MPa and higher. Conclusively, the presence of graphene significantly impacts both the structural and electromechanical properties of copper composites, contributing to enhanced conductivity and mechanical strength. The performance enhancements in Gr/Cu composite wires predominantly depend on the quality and content of graphene, underscoring a critical dependence on these factors. There is a clear need for further optimization of graphene content and processing techniques to fully capitalize on the potential benefits offered by graphene in Gr/Cu composite copper powders. This necessitates a targeted approach to refine these aspects, ensuring maximum performance enhancements in future applications.  
Conceptualization, W.L. and Y.D.; methodology, W.L., Y.D. and Y.H.; validation, J.Z.; investigation W.L., and C.Z.; resources Y.D.; writing--original draft preparation, W.L. and C.Z.; writing--review and editing, W.L. and Y.D.; supervision, Y.H. and Y.D. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Beijing Nova Program (Grant No. Z211100002121086) and the Science and Technology Project of MIIT (TC220A04W-6, 188).  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
This research was supported by the State Key Laboratory of Advanced Power Transmission Technology, the China Electric Power Research Institute, and State grid smart grid research institute Co., Ltd., Beijing, China. We would like to thank [PERSON] and [PERSON] for providing the experimental materials and data processing for this paper.  
Authors [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] were employed by the company State Grid Smart Grid Research Institute Co., Ltd. All authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.