Dislocation microstructure and its influence on corrosion behavior in laser additively manufactured 316L stainless steel

• DOI: 10.1016/j.addma.2021.102263
• Publication Date: 2021-08-20T16:04:47Z
• Authors: David J. Sprouster; W. Streit Cunningham; Gary P. Halada; Hanfei Yan; Ajith Pattammattel; Xiaojing Huang; Daniel Olds; Maryam Tilton; Yong S. Chu; Eric Dooryhee; Guha P. Manogharan; Jason R. Trelewicz
• Keywords: Pitting Corrosion

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