TY - JOUR
T1 - Metastable cellular structures govern localized corrosion damage development in additive manufactured stainless steel
AU - DelVecchio, Evan
AU - Liu, Tiffany
AU - Chang, Yen-Ting
AU - Nie, Yuheng
AU - Eslami, Maryam
AU - Charpagne, Marie-Agathe
N1 - E.D.V., T.L., Y.T.C. and M.A.C. acknowledge the Energy and Biosciences Institute via the EBI-Shell program (corrosion). Y.N. and M.A.C. gratefully acknowledge support from the National Science Foundation, CAREER award DMR-2236640 (synthesis, microstructure characterization, recrystallization). M.E. acknowledges the support from the Illinois Applied Research Institute. We acknowledge the use of facilities and instrumentation at the Materials Research Laboratory Central Research Facilities, University of Illinois. Finally we acknowledge the Imaging Technology Group at the Beckman Institute for their assistance with graphics, imaging, and videos in Fig. 6 and Supplementary Material.
E.D.V., T.L., Y.T.C. and M.A.C. acknowledge the Energy and Biosciences Institute via the EBI-Shell program (corrosion). Y.N. and M.A.C. gratefully acknowledge support from the National Science Foundation, CAREER award DMR-2236640 (synthesis, microstructure characterization, recrystallization). M.E. acknowledges the support from the Illinois Applied Research Institute. We acknowledge the use of facilities and instrumentation at the Materials Research Laboratory Central Research Facilities, University of Illinois. Finally we acknowledge the Imaging Technology Group at the Beckman Institute for their assistance with graphics, imaging, and videos in Fig. and Supplementary Material.
PY - 2024/4/30
Y1 - 2024/4/30
N2 - The rapid solidification associated with additive manufacturing (AM) leads to complex microstructures with peculiar features amongst which cellular solidification structures are the most remarkable. These metastable structures possess a clear segregation pattern dictated by the solidification pathway of the alloy and are bounded by dislocation walls. While they confer exceptional strength and ductility to AM 316L stainless steel, their effect on localized corrosion in chloride environments remains to be established. Here, we employ correlative electron microscopy to reveal coupled chemical, electrochemical, and crystallographic effects on localized corrosion attack and its development. We show that the Cr and Mo-depleted interior of the cellular solidification structures dissolves selectively, giving rise to an intricate damage morphology, that is directly related to the underlying crystallographic orientation. Whereas surface observations only reveal apparently shallow micrometer-size cavities, 3D tomography via focused ion beam serial-sectioning shows a high degree of connectivity between these features underneath the surface. We reveal this intricate morphology, propose a formation mechanism, and discuss alloy design guidelines to mitigate this phenomenon.
AB - The rapid solidification associated with additive manufacturing (AM) leads to complex microstructures with peculiar features amongst which cellular solidification structures are the most remarkable. These metastable structures possess a clear segregation pattern dictated by the solidification pathway of the alloy and are bounded by dislocation walls. While they confer exceptional strength and ductility to AM 316L stainless steel, their effect on localized corrosion in chloride environments remains to be established. Here, we employ correlative electron microscopy to reveal coupled chemical, electrochemical, and crystallographic effects on localized corrosion attack and its development. We show that the Cr and Mo-depleted interior of the cellular solidification structures dissolves selectively, giving rise to an intricate damage morphology, that is directly related to the underlying crystallographic orientation. Whereas surface observations only reveal apparently shallow micrometer-size cavities, 3D tomography via focused ion beam serial-sectioning shows a high degree of connectivity between these features underneath the surface. We reveal this intricate morphology, propose a formation mechanism, and discuss alloy design guidelines to mitigate this phenomenon.
UR - http://www.scopus.com/inward/record.url?scp=85191727206&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85191727206&partnerID=8YFLogxK
U2 - 10.1038/s41529-024-00464-8
DO - 10.1038/s41529-024-00464-8
M3 - Article
SN - 2397-2106
VL - 8
JO - npj Materials Degradation
JF - npj Materials Degradation
IS - 1
M1 - 45
ER -