The decomposition behavior of Ti2SnC synergistically enhances the mechanical properties of graphene copper matrix composites.

In composites, the enhancement of composite properties by a single reinforcer is always limited, while the construction of multi-component composites by synthesizing the characteristics between the components can achieve another breakthrough in composite properties. In this work, Gr @ Cu/Ti₂SnC composites were prepared by chemical vapor deposition and powder metallurgy processes, and the structural design of graphene copper-based composites and the in-situ decomposition properties of Ti₂SnC were combined to achieve a balanced development of composite strength-plastic toughness. The microstructure and mechanical properties of Gr @ Cu/Ti₂SnC composites with different Ti₂SnC contents were systematically investigated. The results show that after densification by SPS sintering, the TiC phase left by the in-situ decomposition of Ti₂SnC becomes an intermediate layer between graphene and Cu matrix, which improves the interfacial bonding between graphene and Cu matrix, and at the same time, the layered graphene can alleviate the distortion field generated by the in-situ decomposition of Ti₂SnC and promote the deflection of cracks, which improves the plasticity and toughness of the composites to a certain extent. With Ti₂SnC content of 9 wt.%, the yield strength and tensile strength reached 308 MPa and 490 MPa, respectively, which were 155% and 108% higher than that of pure copper, and the elongation could still be maintained above 20%.