The effect of the friction stir welding (FSW) parameters on the microstructure and mechanical characteristics of A319 cast Al alloy has been investigated. Plates from the investigated alloy were welded together under different tool rotational (v) and welding (u) speeds. The results showed the possibility of welding and obtaining sound joints from A319 cast Al alloy using FSW. The welded zones exhibited many advantages over the base material (BM) such as, lower porosity content, extra fine non-dendritic a-Al grains, and extra fine more homogeneously dispersed Si particles. The size of both a-Al grains and Si particles was found to be increase by increasing both tool rotational and welding speeds. The welded joints showed better mechanical properties than the BM. It has been found that increasing the tool rotational speed and/or the welding speed reduces both the tensile and yield strengths of the welded joints, however, they still higher than of the BM. In contrast, increasing the aforementioned speeds tends to increase the ductility of the welded joints.
In the present investigation, the microstructure and mechanical characteristics of dissimilar A319 and A356 cast Al alloys plates joined by friction stir welding (FSW) were evaluated. The effect of tool rotational and welding speeds as well as the post-weld heat treatment (PWHT) on such properties was investigated. Post-weld heat treatment was carried out at a solutionising temperature of 540uC for 12 h followed by aging at 155uC for 6 h. For the as welded specimens, the welded zone (WZ) exhibited higher hardness values when compared with the A319 and A356 parent alloys. The peak hardness at the WZ was found to increase by increasing the tool rotational speed and/or reducing the welding speed. In contrast, the post-weld heat treated (PWHTed) specimens exhibited lower hardness values at the WZ than the parent alloys. For PWHTed specimens, the peak hardness at the WZ was found to decrease by increasing the tool rotational speed and/or reducing the welding speed. Tensile tests results demonstrate that, for the as welded specimens, the tensile fracture took place on A356 side where the hardness was minimal. While for PWHTed specimens, the fracture took place at the WZ. Increasing the tool rotational speed reducing both tensile and yield strengths, but increases the ductility of the joint.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.