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Fatigue Microcrack Nucleation Modeling: a Survey of the State of the Art

Mohammad Dabiri(1*), Anssi Laukkanen(2), Timo Björk(3)

(1) Laboratory of steel structures at the Department of Energy Systems, Lappeenranta University of Technology, Finland
(2) VTT Materials and Manufacturing, Research Centre of Finland, Finland
(3) Lappeenranta University of Technology, Finland
(*) Corresponding author


DOI: https://doi.org/10.15866/ireme.v9i4.6231

Abstract


Many different approaches have been proposed for modeling of fatigue crack nucleation and microstructurally short fatigue crack propagation in polycrystalline metals. The mechanisms governing dislocations and slip at micro- and nanoscale have to be taken into account to be able to modify the microstructure of metals and develop materials with improved fatigue resistance. This paper reviews modeling approaches that take the microstructure into the consideration specifically from the fatigue crack nucleation point of view. Key concepts are explained, challenges described, and uncertainties discussed, followed by a comprehensive list of articles on the subject published mainly in the past decade.
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Keywords


Microstructure; Fatigue Crack Nucleation; Crystal Plasticity; Dislocation

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