Abstract
Additive manufacturing (AM) is positioned at a pivotal moment, where its long-promised advantages, e.g., lower cost, reduced environmental burden, and accelerated production, are increasingly tangible yet unevenly realized across industries and regions. This review synthesizes evidence from AM processes for different materials to clarify the technical and economic levers that drive outcomes. Cost performance is shown to depend strongly on design choices, deposition rate, post-processing requirements, and feedstock pricing. Environmental impacts hinge on material production routes, regional energy mix, build utilization, and the extent of material reuse. Lead-time reductions are most significant when components are redesigned for AM, when high-throughput processes are applied to compatible geometries, and when production is geographically localized. Emerging digital tools including machine learning, in situ monitoring, and digital twins are accelerating process stabilization and shortening qualification cycles, while hybrid manufacturing lines demonstrate the value of integrating near-net-shape printing with precision finishing. Drawing from these insights, a pragmatic roadmap is proposed: align parts and supply chains with the most suitable AM processes, decarbonize and streamline feedstock production, and increase system utilization. When these conditions are met, AM can deliver broad, quantifiable improvements in cost efficiency, sustainability, and global adoption. By consolidating fragmented evidence into a unified framework, this review responds to the growing need for clarity as AM moves toward broader industrial deployment.