Exceptional strength-ductility balance and high softening resistance in TiZrNbV/Cu composites via gradient interfacial engineering

This is the authors' abstract. We don't add key points for this paper.

The refractory nature and high positive mixing enthalpies with Cu make TiZrNbV high-entropy alloy (HEA) particles promising candidates for enhancing the thermal stability of Cu matrix composites. In this study, the TiZrNbV/Cu matrix composites containing up to 25 wt% TiZrNbV were fabricated through a vacuum electrical current hot-pressed sintering process. The results showed that the gradient interdiffusion shells containing Cu solid solution, CuTi-rich and NbV-rich phases formed around the TiZrNbV reinforcement particles. The resulting composites demonstrated a remarkable strength-ductility synergy, along with excellent resistance to thermal softening. The 5 wt% TiZrNbV/Cu composite achieved a tensile strength of 305 MPa with 25 % elongation, 78 % IACS conductivity and high softening temperature of 800 °C. The formation of a gradient interdiffusion layer, rather than brittle intermetallics, is identified as the key to achieving strong interfacial bonding and high ductility, which highlights the potential of refractory HEA particles as next-generation reinforcements for high-performance metal matrix composites.