Enhancing Dissimilar Metal Joining: The Role of Aluminum Interlayers in Laser Impact Welding of Mg-Al and Ti Alloys

Joining dissimilar lightweight metals, such as magnesium (Mg) and titanium (Ti), presents critical challenges due to their differing physical properties and limited mutual solubility. This research explores the potential of laser impact welding (LIW) to overcome these barriers by investigating the effects of aluminum (Al) content in Mg-Al alloys, interlayer integration, and the formation of intermetallic phases at the bond interface. Emphasis is placed on understanding how variations in Al composition and the inclusion of an Al interlayer influence the bonding mechanisms between Mg and Ti. Through detailed microstructural analysis and phase identification, this study characterizes the intermetallic phases present at the weld interface, examining their size, distribution, and location. The presence of an Al interlayer was found to significantly improve bonding success, promoting favorable interface morphology and minimizing detrimental intermetallic formation. These findings provide key insights into the underlying mechanisms enabling successful LIW of dissimilar lightweight metals and offer valuable guidance for industrial applications seeking to advance joining strategies in high-performance alloy systems.