according to several studies on friction stir welding the presence of intermetallics in welded zone is harmful and deteriorate the properties of the joint, but in the case of low alloy steel (0.04% C) with pure magnesium welded by this method, the change pure magnesium by AZ61 (Mg–5.8 wt%Al– 0.85 wt%Zn) has significantly increased tensile strength. while there is creation of intermetallic between the steel and the aluminum bitter the equilibrium diagram, can you explain me.
Dissimilar FSW of immiscible materials: Steel/magnesium H. Kasain, Y. Morisada, H. Fujii