On the Characteristics of Friction Stir Welding Lap Joint of Magnesium and Aluminum

Lap joints of commercially pure magnesium plates to aluminium plates (Magnesium plate on the top, and Aluminium plate, grade ۱۱۰۰, on the bottom side) were conducted by friction stir welding using various traveling and rotation speeds of the tool to investigate the effects of the welding parameters on the joint characteristics and strength. Defect-free lap joints were obtained in the welding traveling speed range of ۴۰-۸۰ mm/min, and rotational speed range of ۱۲۰۰-۱۶۰۰ rpm. The shear tensile strength of Mg/Al joints increased as a result of decreasing the welding speed from ۱۲۰ to ۴۰ mm/min at constant rotation speed of ۱۶۰۰ rpm.  Defects such as surface grooves, excessive flash, tunnels, and voids were observed if the joints prepared out of the mentioned range. The effects of the welding parameters are discussed metallographically based on observations with optical and scanning electron microscopes.

کلیدواژه ها:

Frictions stir welding ، Mg/Al ، Dissimilar ، Lap joint ، Defects ، Intermetallic