Targeted microstructural authoring through additive manufacturing of metals

Metal three-dimensional printing, also known as additive manufacturing (AM), presents an innovative opportunity for materials engineers to locally tailor the microstructure of engineering alloys over diverse length scales. This article examines the predominance of laser powder bed fusion (L-PBF) among various metal AM processes and its potential to enable localized metallurgical authoring through manipulation of processing parameters and advanced beam shaping technologies. By locally controlling the cooling rates during phase transformations, L-PBF alters the thermal history of the materials being created, thereby influencing their microstructural characteristics. Strategies for tailoring microstructure are discussed within the context of the established processing-structure-properties paradigm of materials science, despite the necessity for specialized equipment. The potential for site-specific mechanical property optimization in high-performance engineering components is also analyzed, reflecting on the implications of these emerging strategies in the broader landscape of additive manufacturing for advanced materials engineering.