Effect of Composition and Processing on Properties of 8030 Aluminum Alloy Single Wire

Regarding the issue of non-compliance with the performance of single wires (tensile strength ranging from 98 N·mm⁻² to 159 N·mm⁻² and number of repeated bending being not less than 25) after stranding of aluminum alloy conductors in GB/T 31840 series standards, influence of chemical composition (mass fractions of Cu, Fe) and processing technology of 8030 aluminum alloy on its relevant properties was systematically investigated. Results showed that the addition of Cu (mass fractions of 0.16%~0.22%) could enhance tensile strength but significantly deteriorate number of repeated bending (a reduction of over 30%). Increasing mass fractions of Fe could improve tensile strength but adversely affect material workability. Prolonged annealing (holding hour greater than 6 h) at 380 °C could reduce number of repeated bending due to grain growth and brittle phase segregation. However, an optimized composition with medium-Fe low-Cu (mass fractions of 0.60% Fe and 0.16% Cu) combined with a 3-hour annealing process could achieve a balanced compliance in both tensile strength and number of repeated bending for stranded conductor wires. Besides, changes in surface morphology of compacted conductor strands after stranding could lead to a decrease in tensile strength. The research could provide theoretical foundations and practical guidance for composition design, annealing process optimization, and production control of aluminum alloy conductors.