Facile synthesis of high-performance carbon nanosheet/Cu composites from copper formate

Recently, much research has been reported on the fabrication of carbon-nanofiller (e.g., carbon nanotube (CNT), carbon nanosheet (CNS), and graphene)-reinforced copper matrix composites due to their wide potential applications. However, the preparation processes are generally complicated and difficult for commercial applications. Here, we propose a facile method to fabricate CNS-reinforced copper matrix composites by directly pyrolyzing copper formate powder at high temperature and then consolidating by spark plasma sintering. Interestingly, a complex interface consisting of CNSs, Cu nanoparticles, and CuO nanoparticles is found in the composite. The as-sintered CNS/Cu composite containing 0.27 vol% CNSs has a tensile yield strength of 498 +/- 2 MPa and an electrical conductivity of 80.8 +/- 0.1% International Annealed Copper Standard. The analysis of strengthening mechanism indicates that 51% of the tensile yield strength is contributed by the complex interface. The introduction of H-2 during the pyrolyzing copper formate process results in an increase on the elongation and conductivity of CNS/Cu composite. After rolling, the elongation of CNS/Cu composite is as high as 8.5% and the friction coefficient is 0.25. This work provides a new guideline to the facile fabrication and interfacial design of advanced carbon-nanofiller-reinforced metal matrix composites with high performance. (c) 2020 Elsevier Ltd. All rights reserved.