Improved strength and conductivity of metallic-glass-reinforced nanocrystalline CuCrZr alloy

Metallic glass (MG)-particle-reinforced nanocrystalline CuCrZr alloys with ultrahigh strengths and good conductivities are designed and synthesized via mechanical milling and spark plasma sintering (SPS). The particle morphology and dispersion state of the CuZrAl MG reinforcement in the CuCrZr alloy matrix are optimized by regulating the milling time of the composite powders prior to SPS consolidation. Outstanding properties are achieved by 5 h and 10 h milling processes with ultimate compressive strengths of 1099 ± 33 and 1185 ± 29 MPa and high conductivities of 29.9 ± 0.8% IACS and 25.2 ± 0.6% IACS, respectively. According to the quantified results of strengthening and conductivity mechanisms, MG reinforcements and ultrafine grains are responsible for the balance of superior strength and conductivity of the composites.