MATEC Web of Conferences
Volume 14, 2014EUROSUPERALLOYS 2014 – 2nd European Symposium on Superalloys and their Applications
|Number of page(s)||7|
|Section||Posters: Deformation and Damage Mechanisms II: Fatigue, Oxidation, Crack Propagation|
|Published online||29 August 2014|
Fatigue crack initiation in nickel-based superalloys studied by microstructure-based FE modeling and scanning electron microscopy
1 MTU Aero Engines AG, 80995 Munich, Germany
2 Friedrich-Alexander-Universität Erlangen-Nürnberg, Department of Materials Science and Engineering, Institute of General Material Properties WW1, 91058 Erlangen, Germany
3 Zentralinstitut für Neue Materialien und Prozesstechnik ZMP, 90762 Fürth, Germany
4 Now at University of Applied Sciences Augsburg, Faculty of Electrical Engineering, 86161 Augsburg, Germany
a Corresponding author: firstname.lastname@example.org
In this work stage I crack initiation in polycrystalline nickel-based superalloys is investigated by analyzing anisotropic mechanical properties, local stress concentrations and plastic deformation on the microstructural length scale. The grain structure in the gauge section of fatigue specimens was characterized by EBSD. Based on the measured data, a microstructure-based FE model could be established to simulate the strain and stress distribution in the specimens during the first loading cycle of a fatigue test. The results were in fairly good agreement with experimentally measured local strains. Furthermore, the onset of plastic deformation was predicted by identifying shear stress maxima in the microstructure, presumably leading to activation of slip systems. Measurement of plastic deformation and observation of slip traces in the respective regions of the microstructure confirmed the predicted slip activity. The close relation between micro-plasticity, formation of slip traces and stage I crack initiation was demonstrated by SEM surface analyses of fatigued specimens and an in-situ fatigue test in a large chamber SEM.
© Owned by the authors, published by EDP Sciences, 2014
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.