ABSTRACT
Successful additive manufacturing (AM) of aluminum alloys has been demonstrated using a number of processes, which is the focus of this article. Utilization of some aluminum alloys with relatively low reflectivity coupled with process optimization to achieve high retained energy densities enabled the successful deposition of aluminum–silicon alloys that were previously manufactured exclusively using casting processes. The design flexibility of AM processes coupled to the ability to direct energy and material to specific spatial locations has also been used to demonstrate the ability to join dissimilar aluminum alloys, with applicability toward functional grading and repair. Researchers have shown that the additively manufactured alloys exhibit comparable and, in cases, improved mechanical properties to their conventional counterparts with highly refined grain structures. Elaborate investigations into their microstructures to determine the causality of the mechanical properties are also discussed in detail. Understanding the relationship between these desired high retained energy densities and the factors favoring them, including the alloy composition, input energy, and the deposition speed and volume, plays a pivotal role toward successful additive manufacture. With further process parameter optimization and the development of raw material supply chains that can create and tailor alloys based on need, the applicability of these AM processes can be adapted to many more aluminum alloys and can be tailored to serve a wide range of industries.
