Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorDaudin, R-
dc.contributor.authorTerzi, S-
dc.contributor.authorLhuissier, P-
dc.contributor.authorTamayo, J-
dc.contributor.authorScheel, M-
dc.contributor.authorNadendla, H-
dc.contributor.authorEskin, D-
dc.contributor.authorSalvo, L-
dc.identifier.citationActa Materialiaen_US
dc.description.abstractThe study of dendritic growth is a challenging topic at the heart of intense research in material science. Understanding such processes is of prime importance as it helps predicting the final microstructure governing material properties. In the specific case of the design of metal-matrix nanocomposites (MMNCs), the addition of nano-sized particles inside the metallic melt increases the complexity as their influence on the growth morphology of dendrites is not yet fully understood. In the present experimental study, we use in situ X-ray tomography imaging with very high temporal resolution (0.35 s per 3D image) coupled with in situ ultrasonic melt homogenisation to record, in 3D and real time, the free growth at high cooling rates (~2 K.s-1) of equiaxed dendrites in an AA6082 alloy containing Y2O3 nanoparticles. The careful 3D analysis of the dendrite morphologies as well as their solidification dynamics reveals that in the case of well-dispersed particles, dendrite equiaxed growth occurs through complex hyper-branched morphologies. Such behaviour is believed to arise from particle-induced modification of the solidification processes at the origin of multiple splitting, branching and curving mechanisms of the dendrite arms. These results shed light on long-standing empirical and modelling statements and open new ways for direct investigation of equiaxed growth in metallic alloys and composites.en_US
dc.description.sponsorshipThe authors wish to acknowledge financial support from the ExoMet Project, which is co-funded by the European Commission in the 7th Framework Program (contract FP7-NMP3-LA-2012-280421) by the European Space Agency and by the individual partner organizations. They also wish to acknowledge the ESRF-MA1876 long term project, E. Boller and A. Rack from ESRF-ID19 beam line, for providing strong support concerning the development and test of the dedicated set-up as well as facilitating reconstruction procedure and 3D analysisen_US
dc.subjectAl alloysen_US
dc.subjectMetal matrix composites (MMCs)en_US
dc.subjectSynchrotron radiation computed tomographyen_US
dc.subjectSolidification microstructuresen_US
dc.subjectEquiaxed dendrites morphologiesen_US
dc.titleParticle-induced morphological modification of Al alloy equiaxed dendrites revealed by sub-second in situ microtomographyen_US
dc.relation.isPartOfActa Materialia-
Appears in Collections:Dept of Mechanical Aerospace and Civil Engineering Research Papers

Files in This Item:
File Description SizeFormat 
FullText.pdfEmbargoed untill 18/12/20181.31 MBAdobe PDFView/Open

Items in BURA are protected by copyright, with all rights reserved, unless otherwise indicated.