Print Email Facebook Twitter Self healing of creep-induced damage in Fe-3Au-4W by multiple healing agents studied by synchrotron X-ray nano-tomography Title Self healing of creep-induced damage in Fe-3Au-4W by multiple healing agents studied by synchrotron X-ray nano-tomography Author Fu, Y. (TU Delft Novel Aerospace Materials) Fang, H. (Université Grenoble Alpes) Monaco, F. (European Synchrotron Radiation Facility) Cloetens, P. (European Synchrotron Radiation Facility) Tichelaar, F.D. (TU Delft QN/Afdelingsbureau; Kavli institute of nanoscience Delft) van Meel, J.G. (TU Delft Lab Geoscience and Engineering) Brück, E.H. (TU Delft RST/Fundamental Aspects of Materials and Energy) van der Zwaag, S. (TU Delft Novel Aerospace Materials; Tsinghua University) van Dijk, N.H. (TU Delft RST/Fundamental Aspects of Materials and Energy) Date 2022 Abstract Constant stress creep experiments at 550 °C were performed on a high-purity Fe-3Au-4W (wt.%) ternary alloy with about 1 at.% supersaturation for Au and W in order to study self healing of grain-boundary cavities by both Au-rich and W-rich precipitates. Using synchrotron X-ray nano-tomography, the development of the creep cavities and the healing precipitates at different stages of creep was visualised using two spatial resolutions (30 and 100 nm voxel size) for separate samples taken after different loading times. The healing kinetics was found to strongly depend on the nucleation time of the cavities. Cavities nucleated at an early stage of creep could be fully healed, while the healing of the late-nucleated cavities is much slower due to a decrease in the diffusional flux of the healing supersaturated solutes over time, as a result of (i) a decrease in inter-cavity spacing caused by cavity nucleation and (ii) a gradual depletion of the supersaturated solutes near the grain boundaries. The interaction between the competing healing mechanisms for creep cavities by Au-rich and W-rich precipitates is discussed. It was found that Au-rich precipitates are formed much faster than the W-rich precipitates, and thereby effectively provide creep damage healing on different time scales. Subject Creep damageSelf-healingTernary alloysTomographyX-ray synchrotron radiation To reference this document use: http://resolver.tudelft.nl/uuid:da48b54f-896e-408a-8cf5-526d50a38043 DOI https://doi.org/10.1016/j.actamat.2022.118266 ISSN 1359-6454 Source Acta Materialia, 239 Part of collection Institutional Repository Document type journal article Rights © 2022 Y. Fu, H. Fang, F. Monaco, P. Cloetens, F.D. Tichelaar, J.G. van Meel, E.H. Brück, S. van der Zwaag, N.H. van Dijk Files PDF 1_s2.0_S1359645422006462_main.pdf 4.63 MB Close viewer /islandora/object/uuid:da48b54f-896e-408a-8cf5-526d50a38043/datastream/OBJ/view