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.