Surface Finishing Of PBF-LB Stainless Steels Using Chemical And Chemical-Mechanical Polishing In Combination With Hot Isostatic Pressing (HIP) For Improved Mechanical Performance

Abstract

Additive manufacturing (AM) enables the production of metal components with complex geometries; however, surface and near-surface defects inherent to powder-based processing limit mechanical performance and component qualification. Surface-related features, such as partially fused particles and near-surface porosity, significantly reduce fatigue life, thereby restricting adoption in high-reliability applications. Improving surface quality through chemical polishing (CP) and chemical-mechanical polishing (CMP) provides a viable pathway to enhance structural reliability. This study evaluates CP and CMP in combination with hot isostatic pressing (HIP) as strategies to mitigate surface and subsurface defects in PBF-LB\17-4 PH, 15-5 PH, and 316L. The influence of surface roughness and microstructural evolution on tensile properties and high-cycle fatigue performance was examined. Results demonstrate clear process–structure–property relationships linking powder-derived surface condition, post-processing strategy, and mechanical performance. These findings support robust, qualification-ready post-processing routes for AM stainless steel components. This work was supported by the USAF-SBIR Program under Contract FA864923P1086.