Effect of welding wire compositions on microstructures and mechanical properties of welded joint of 2519 aluminum alloy

2519 aluminum alloy was welded using ER4047 and ER2319 welding wire with the method of MIG welding.Mechanical properties and microstructures of welded joint were studied.The results show that the weldability of the 2519 aluminum alloy with ER2319 welding wire is better than that with ER4047 welding wire; the microstructures of weld metal is more refined with ER2319 welding wire than that with ER4047;The mechanical properties of welded joint is worse than that of base metal, the weld zone is the weakest point of welded joint, The soften zone in heat-affected zone(HAZ)is the second weakest zone of welded joint, which is formed due to the overaging of the main strengthening phase particles leading to coarsening.