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Solute Clustering in Multi-Component Aluminium Alloys Rosen Ivanov

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Solute Clustering in Multi-Component Aluminium Alloys Rosen Ivanov Solute clustering in multi-component aluminium alloys Rosen Ivanov To cite this version: Rosen Ivanov. Solute clustering in multi-component aluminium alloys. Materials. Université Grenoble Alpes, 2017. English. NNT : 2017GREAI012. tel-01688296 HAL Id: tel-01688296 https://tel.archives-ouvertes.fr/tel-01688296 Submitted on 19 Jan 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE Pour obtenir le grade de DOCTEUR DE LA COMMUNAUTÉ UNIVERSITÉ GRENOBLE ALPES Spécialité : Ingénierie Matériaux Mécanique Energétique Environnement Procédé Production Arrêté ministériel : 25 mai 2016 Présentée par Rosen IVANOV Thèse dirigée par Frédéric DE GEUSER et codirigée par Alexis DESCHAMPS préparée au sein du Laboratoire de Sciences et Ingénierie des Matériaux et des Procédés (SIMaP) dans l'École Doctorale Ingénierie – Matériaux Mécanique Energétique Environnement Procédés Production (I-MEP2) Solute clustering in multi- component aluminium alloys Thèse soutenue publiquement le 10 févier 2017, devant le jury composé de : Prof. John BANHART Professeur à Helmholtz Zentrum Berlin, Président Prof. Michel PEREZ Professeur à Université de Lyon, Rapporteur Dr. Xavier SAUVAGE Directeur de recherche CNRS à Université de Rouen, Rapporteur Dr. Myriam DUMONT Maître de conférences à l’Université Aix-Marseille, Examinateur Dr. Frédéric DE GEUSER Chargé de recherche CNRS à Université Grenoble Alpes, Directeur Prof. Alexis DESCHAMPS Professeur à Université Grenoble Alpes, Co-directeur Dr. Christophe SIGLI Ingénieur de recherche à C-Tech Constellium, Invité Table of Contents Preface and contribution of authors ............................................................................................ 1 1 Introduction ......................................................................................................................... 3 1.1 Definition of ‘solute clusters’ ...................................................................................... 4 1.2 Thesis approach ............................................................................................................ 5 1.3 References .................................................................................................................... 6 2 Literature review ................................................................................................................. 7 2.1 A solid solution and the basics of precipitation ........................................................... 7 2.2 Solute clusters ............................................................................................................ 10 2.2.1 Solute clusters in the Al-Cu-Mg system ............................................................. 11 2.2.2 Solute clusters in Al-Cu-Li-X system ................................................................. 14 2.2.3 Some specific cases of solute clusters ................................................................ 15 2.3 Characterisation of solute clusters ............................................................................. 16 2.4 Conclusions ................................................................................................................ 18 2.5 References .................................................................................................................. 19 3 Materials and experimental methodology......................................................................... 29 3.1 Materials employed .................................................................................................... 29 3.2 Thermal processing for clustered states ..................................................................... 30 3.3 Standard metallurgy procedures ................................................................................. 32 3.4 Differential scanning calorimetry .............................................................................. 32 3.4.1 DSC equipment used .......................................................................................... 33 3.4.2 DSC procedures and data interpretation ............................................................. 33 3.5 Small angle scattering ................................................................................................ 37 3.5.1 Instrumentation ................................................................................................... 37 3.5.2 Experimental procedure ...................................................................................... 38 3.5.3 Data processing ................................................................................................... 40 3.6 Atom probe tomography ............................................................................................ 40 3.6.1 Instrument ........................................................................................................... 41 3.6.2 Experimental procedure ...................................................................................... 41 3.7 References .................................................................................................................. 41 4 A combined characterization of clusters in naturally aged Al-Cu-(Li, Mg) alloys using small-angle neutron and X-ray scattering and atom probe tomography ................................... 45 4.1 Introduction ................................................................................................................ 45 i 4.2 Materials and experiments ......................................................................................... 46 4.3 Data interpretation ...................................................................................................... 48 4.3.1 General framework ............................................................................................. 48 4.3.2 The model for correlation function γ(r) .............................................................. 49 4.3.3 Corresponding intensity I(q) ............................................................................... 50 4.3.4 Expression of the mean square fluctuation .................................................... 51 4.3.5 The radial distribution function from atom probe tomography and the correlation � function 53 4.4 Results ........................................................................................................................ 53 4.4.1 Solute correlations obtained from APT .............................................................. 53 4.4.2 Experimental results from SANS and SAXS ...................................................... 55 4.4.3 Application of the model to the SAXS and SANS data...................................... 56 4.5 Discussion .................................................................................................................. 56 4.6 Conclusion .................................................................................................................. 58 4.7 References .................................................................................................................. 58 5 Clustering kinetics during natural ageing of Al-Cu-(Li, Mg) alloys ................................ 67 5.1 Introduction ................................................................................................................ 67 5.2 Materials and experimental methodology .................................................................. 68 5.3 Results ........................................................................................................................ 71 5.3.1 Natural age hardening ......................................................................................... 71 5.3.2 Differential scattering calorimetry ...................................................................... 72 5.3.3 Small angle scattering ......................................................................................... 75 5.3.4 Temporal evolution of scattering intensity ......................................................... 76 5.3.5 Temporal evolution of cluster properties ............................................................ 77 5.4 Discussion .................................................................................................................. 82 5.5 Conclusion .................................................................................................................. 84 5.6 References .................................................................................................................. 84 6 Thermal stability and post-reversion formation of solute clusters in Al-Cu-(Li, Mg) alloys 89 6.1 Introduction ................................................................................................................ 89 6.2 Materials and experimental methodology .................................................................. 90 6.3 Results ........................................................................................................................ 91 6.3.1 Thermal
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