Microstructure Observation of Weld Interface between 6063 Al alloy and S45C Carbon Steel by Means of Friction Stirring

-Study on Welding in Dissimilar Metals by Means of Friction Stirring (2nd Report)-

Abstract

Microstructure of weld interface between 6063 and S45C by means of friction stirring was observed by TEM. The reaction layer was formed along welding direction and depth direction of tool insert. The layers were composed of various intermetallic compounds such as Fe₂Al₅ and FeAl. The constitution differed with welding conditions. At 500 mm/min of welding speed, the interface had a thin reaction layer. At 1000 mm/min of welding speed, the interface had layered structure. However, both of the weld interfaces had a reaction layer under 1 μm and achieved high tensile strength of weld joint.