Study on the new joining technology of aluminum alloy / Q235 steel dissimilar metal by the longitudinal electromagnetic hybrid TIG welding-brazing method

A new longitudinal electromagnetic hybrid TIG welding-brazing method is adapted to aluminum alloy / low carbon steel dissimilar metals joining experiments. The microstructure and element diffusion are analyzed in the arc fusion-brazing welding joint. As a result that the aluminum alloy / low carbon steel dissimilar metals complete a tight TIG welding-brazing joint by the longitudinal electromagnetic controlling. The second phase particles distribute uniformly in the welding seam. And the size of grain is much smaller than that of normal TIG - brazing welding seam. Both of Fe and Al elements are less diffused on the aluminum alloy / low carbon steel dissimilar metals interface. But Si element has a relatively high percentage on the welding interface, and the diffusion distance of Si element is very short in the welding seam. So the longitudinal electromagnetic hybrid TIG welding-brazing method can be adopted to achieve a high-quality welding joint of aluminum alloy / low carbon steel dissimilar metals.