The hierarchical nature of additively manufactured materials necessitates a multimodal approach for quantifying microstructural features and corresponding chemical heterogeneities that ultimately impact their properties and performance. In laser powder-bed fusion (L-PBF) 316L stainless steel, corrosion behavior has been discussed in the context of chemical heterogeneities formed in the presence of these hierarchical microstructures. Here, we employ a suite of advanced synchrotron x-ray techniques and correlative transmission electron microscopy for the analysis of microstructure and chemical heterogeneities in L-PBF 316L as a function of printing speed. Our findings reveal an appreciable dislocation density consistent with the formation of a cellular dislocation microstructure in L-PBF 316L, which is correlated to spatial variations in the local Cr concentration and the formation of complex Mn₇C₃ nanoinclusions. Cyclic voltammetry experiments reveal that relative to wrought 316L, the printed samples exhibit either a comparable or marginally reduced susceptibility to uniform corrosion but with an increased affinity for pitting particularly in the samples printed at the highest speed with the largest dislocation density. Given the spatial correlations between regions of high dislocation density and the formation of chemical heterogeneities known to degrade corrosion performance, our findings demonstrate the impact of the microstructural defect state and its variation with printing speed on the resistance of L-PBF 316L to uniform and localized corrosion.

增材制造材料的分层性质需要一种多模态方法来量化微观结构特征和相应的化学异质性，这些化学异质性最终会影响其性能和性能。在激光粉末床融合 (L-PBF) 316L 不锈钢中，已经在存在这些分级微观结构时形成的化学异质性的背景下讨论了腐蚀行为。在这里，我们采用一套先进的同步加速器 X 射线技术和相关透射电子显微镜来分析 L-PBF 316L 中作为打印速度函数的微观结构和化学异质性。我们的研究结果揭示了可观的位错密度，与 L-PBF 316L 中细胞位错微结构的形成一致，₇ C ₃纳米夹杂物。循环伏安法实验表明，相对于锻造 316L，打印的样品对均匀腐蚀的敏感性相当或略有降低，但对点蚀的亲和力增加，尤其是在以最高速度打印且位错密度最大的样品中。鉴于高位错密度区域与已知会降低腐蚀性能的化学异质性的形成之间的空间相关性，我们的研究结果证明了微观结构缺陷状态及其随打印速度的变化对 L-PBF 316L 对均匀和局部化的抵抗力的影响腐蚀。