Combined effect of inoculation and magnetic are oscillation on microstructure and tensile behaviour of type 2090 Al-Li alloy weld fusion zones

In the development of Al-Li alloys for aerospace structures, their behaviou r during welding plays an important role. One way of improving weldability is to refine weld solidification structures, which can be achieved by a var iety of means. In this work, a type 2090 Al-Li alloy was gas tungsten arc w elded with two different filler materials corresponding to types 2319 (Al-6 .3 Cu) and 4043 (Al-5.2 Si). Inoculation with titanium together with arc os cillation through an imposed alternating magnetic field was used to refine the weld fusion zone microstructures. Post-weld aging and tensile testing w ere employed to assess possible improvements in performance. It was found t hat the combined treatment of inoculation and magnetic oscillation resulted in fully equiaxed,fine grained structures and that this led to a noticeabl e increase in aging response and tensile properties, especially ductility.