From defects to Performance: A Dual-Framework approach to Post-Processing optimization in additively manufactured stainless steel

Additive manufacturing (AM) enables the production of stainless-steel components with unprecedented geometric complexity; however, industrial adoption remains constrained by process-induced defects, including porosity, residual stresses, microstructural heterogeneity, and poor surface integrity. Although numerous post-processing technologies have been developed, current selection approaches remain largely empirical and insufficiently linked to defect mechanisms and targeted performance outcomes. This review critically analyses 110 studies published between 2015 and 2025 and proposes a Dual-Framework Decision Architecture for the rational selection of post-processing strategies in additively manufactured stainless steels. The first framework maps technologies according to bulk integrity and surface functionality, while the second links AM defects to engineering objectives, processing routes, expected benefits, and trade-offs. The analysis demonstrates that no individual technology can optimise all performance domains. Hot Isostatic Pressing provides near-complete densification but may reduce strength through microstructural coarsening. Electropolishing and advanced electrochemical routes improve surface quality and corrosion resistance, whereas severe shot peening enhances fatigue performance through deep compressive residual stresses. The findings show that optimal performance depends on hybrid post-processing chains combining complementary technologies. By integrating defect mitigation, process selection, and performance engineering, the proposed architecture establishes post-processing as a strategic design variable for next-generation AM systems.