The Journal of Physical Chemistry C · 2023 · 18 citations · 33 references
Natural SciencesMaterials EngineeringMaterials ScienceCorrosion ScienceMetallic MaterialsMetallurgyCorrosion EngineeringCorrosion MechanismsCorrosion-resistant MaterialsElectrochemical CorrosionLocalized CorrosionMetalsAnodic DissolutionCorrosion BehaviorCorrosion CellsElectrochemical MechanismsGrain BoundariesGrain Boundary CorrosionHydrogen EmbrittlementMicrostructure-corrosion Relationships
Grain boundary (GB) corrosion of Al alloy is often ascribed to the anodic dissolution of nanoscale MgZn 2 precipitates formed along the GB. However, this reaction has not been confirmed by direct observation and does not explain the subsequent process to form a large-scale pit. Here, we clarify these points by directly visualizing changes in nanoscale structures and potential (∼local corrosion cell) distributions during the GB corrosion in the H 2 SO 4 solution by open-loop electric potential microscopy (OL-EPM). The potential images unambiguously confirm the anodic dissolution of the MgZn 2 precipitates induced by immersion into the H 2 SO 4 solution. In addition, we found that erosion of the GB after MgZn 2 dissolution is driven by hydrogen embrittlement (HE) until another underlying MgZn 2 precipitate is exposed. These nanolevel understandings should help improve the susceptibility of Al alloys to stress corrosion cracking originating from the GB corrosion.
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M. Nonnenmacher, M. O’Boyle, H. K. Wickramasinghe · Applied Physics Letters · 1991 · 2.3K citations
Natural Sciences, Materials Engineering, Materials Science +17
Recent development in aluminium alloys for aerospace applications
A. Heinz, A. Haszler, C. Keidel et al. · Materials Science and Engineering A · 2000 · 1.3K citations
Engineering, Aerospace Engineering, Materials Engineering +16