Abstract: 7A52 aluminum alloy was welded using traditional ER5183 welding wires and selfmade 5183 welding wires containing Sc， Er and Sc/Er by TIG welding method. Mechanical properties and microstructures of the welded joints were studied. The results showed that all the tensile fracture occurred in the center of the weld joints and the weld zone was the weakest link in the weld joints， followed by the soften zone in the heataffected zone. The additions of Sc and Er to ER5183 welding wire fined grains of weld joints significantly and increased the strength of the welded joint. The best result was achieved with the addition of Sc independently， followed by the addition of Er alone. The tensile strength of the welded joints reached 3324MPa， and was 725% of that of the base material.

Key words: weld joint, microalloying, microstructure, mechanical properties, 7A52 alloy