Effects of pre-strain and pre-aging treatments on microstructure and properties of 6101 aluminum alloy used for electrical conductor

In the present work, pre-strain and pre-aging treatments were performed on the basis of artificial aging treatment in order to enhance the mechanical properties and electrical conductivity of 6101 aluminum alloy. Microstructures, conductivity and mechanical properties of the alloy subjected to various treatments (solution treating + aging, solution treating + pre-strain + aging and solution treating + pre-aging + pre-strain + re-aging) were investigated. The results reveal that the ultimate tensile strength and electrical conductivity of the 6101 alloy subjected to 60% cold rolling and aged at 180℃ for 6 h reach 262 MPa and 55.7% IACS, respectively, which are superior to those of the alloy after conventional artificial aging. And the properties can be further enhanced to 289 MPa and 58.0% IACS when the alloy is pre-aged at 180℃ for 2hr and then 70% cold rolled followed by re-aged at 180℃ for 6 hr. The simultaneously enhanced strength and conductivity are chiefly attributed to the interaction of strain hardening and precipitation strengthening.