Quantitative mechanisms behind the high strength and electrical conductivity of Cu-Te alloy manufactured by continuous extrusion

The microstructure,mechanical performance,and electrical conductivity of Cu-Te alloy fabricated by continuous extrusion were quantitatively investigated.The results demonstrate that the grain size of the Cu-Te alloy is refined significantly by incomplete dynamic recrystallization.The Cu2Te phase stimulates recrystallization and inhibits subgrain growth.After extrusion,the tensile strength increases from217.8±4.8 MPa to 242.5±3.7 MPa,the yield strength increases from 65.1±3.5 MPa to 104.3±3.8 MPa,and the yield to tensile strength ratio is improved from 0.293±0.015 to 0.43±.0.091,while the electrical conductivity of room temperature decreases from 95.8±0.38%International Annealed Cu Standard(IACS)to 94.0%±0.32%IACS.The quantitative analysis shows that the increment caused by dislocation strengthening and boundary strengthening account for 84.6%of the yield strength of the extruded Cu-Te alloy and the electrical resistivity induced by grain boundaries and dislocations accounts for 1.6%of the electrical resistivity of the extruded Cu-Te alloy.Dislocations and boundaries contribute greatly to the increase of yield strength,but less to the increase of electrical resistivity.