Review on Friction Stir Welding of Dissimilar Magnesium and Aluminum Alloys: Scientometric Analysis and Strategies for Achieving High-Quality Joints

• Published in: Journal of magnesium and alloys 2023-11, Vol.11 (11), p.4082-4127
• Main Authors: Ahmed, Mohamed M.Z., El-Sayed Seleman, Mohamed M., Fydrych, Dariusz, ÇAM, Gürel
• Format: Article
• Language: English
• Subjects: Al-alloys; Dissimilar material welding; Friction stir welding (FSW); Intermetallics; Mg-alloys; Weld performance
• ISSN: 2213-9567; 2213-9567
• DOI: 10.1016/j.jma.2023.09.039

•The FSW parameters are the primary factor for controlling the dissimilar Mg/Al joint quality.•The use of the Zn interlayer is found to be significantly effective in enhancing the dissimilar Mg/Al joint quality.•The main effect of the Zn interlayer in enhancing the Mg/Al joint quality is based on metallurgical bonding rather than mechanical interlocking.•EAFSW gave promising results in improved tensile strength and elimination of defects of Mg/Al joints.•The submerged FSW (SFSW) effectively controls heat generation. Magnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds (IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar Al-Mg joining due to the inherent low heat inputs involved in the process. However, the IMCs, namely Al3Mg2 and Al12Mg17 phases, have also been reported to form during Al-Mg dissimilar FSW; their amount and thickness depend on the heat input involved; thus, the weld parameters used. Since the heat dissipated in the material during the welding process significantly affects the amount of IMCs, the heat input during FSW should be kept as low as possible to control and reduce the amount of IMCs. This review aims to critically discuss and evaluate the studies conducted in the dissimilar Al/Mg FSW through a scientometric analysis and also with a focus on the strategies recently applied to enhance joint quality. The scientometric analysis showed that the main research directions in Mg/Al FSW are the technological weldability of aluminum and magnesium during FSW, structural morphology, and mechanical properties of dissimilar welded joints. Considering the scope of application of the aforementioned joints, the low share of articles dealing with environmental degradation and operational cracking is surprising. This might be attributed to the need for well-developed strategies for obtaining high-quality and sustainable joints for applications. Thus, the second part of this review is conventional, focusing mainly on the new strategies for obtaining high-quality Mg/Al joints. It can be concluded that in addition to the necessity to optimum welding parameters to suppress the excessive heat to limit the amount and thickness of IMC fo