Fabrication of Cu-Ta composite with high strength and electrical conductivity through thermomechanical processing

Cu-Ta composites exhibit superior overall performance and application potential, but research and fabrication related to conductors remain limited. In current work, Cu_100-xTa_x (x = 10, 15, 20, 25 wt%) composites were fabricated through the combination of powder metallurgy, followed by rotary swaging and drawing at relatively low strain. The effects of Ta content on the microstructure evolution, mechanical and electrical properties were investigated. The microstructure of Cu-Ta composite with elongated Cu grain exhibited enhanced Ta particle dispersion during plastic deformation stages. The deformation texture of the Cu matrix can be found along with longitudinal section. The average size of partial Ta nanoparticles reduces to 24.8 nm in the approximate center region. The increasing of Ta content could promote Cu grain refinement and improve mechanical strength, but reduce plasticity of Cu-Ta composites. With increasing Ta content from 10 to 25 wt%, the ultimate tensile strength, Vickers hardness, and compressive yield strength reach ranges of 379–498 MPa, 123.7–159.4 HV, and 315–411 MPa, respectively. Despite the slight decrease of electrical conductivity caused by existence of Ta phase, the conductivity of all composites exceeded 68 % IACS. The results could provide valuable insights for fabricating Cu-based composites aiming to the wire form application.