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Institutional Repository - Research Portal Dépôt Institutionnel - Portail De La Recherche Institutional Repository - Research Portal Dépôt Institutionnel - Portail de la Recherche University of Namurresearchportal.unamur.be THESIS / THÈSE DOCTOR OF SCIENCES Processing of transparent YAG and BaTiO3 ceramics by SPS Author(s) - Auteur(s) : Moronta Perez, Rosa Award date: 2018 Awarding institution: University of Namur Supervisor - Co-Supervisor / Promoteur - Co-Promoteur : Link to publication Publication date - Date de publication : Permanent link - Permalien : Rights / License - Licence de droit d’auteur : General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. BibliothèqueDownload date: Universitaire 24. sept.. 2021 Moretus Plantin UNIVERSITY OF NAMUR FACULTY OF SCIENCES Namur, Belgium Processing of transparent YAG and BaTiO3 ceramics by SPS Author: ROSA MORONTA PEREZ Members of the jury: Pr. LAURENT HOUSSIAU (President) Pr. PAOLA PALMERO Dr. CLAUDE ESTOURNES Dr. PHILIPPE AUBRY Pr. OLIVIER DEPARIS Dr. FRANCIS CAMBIER Dr. LAURENT BOILET (Co-supervisor) Pr. LUC HENRARD (Supervisor) Doctoral Thesis January 2018 UNIVERSITY OF NAMUR BELGIAN CERAMIC RESEARCH FACULTY OF SCIENCES CENTRE Namur, Belgium Mons, Belgium Processing of transparent YAG and BaTiO3 ceramics by SPS Ph. D. supported by the Walloon Region (DG06) and the ESF First DOCA program (Convention ECV320600FD017F/1217883) Author: ROSA MORONTA PEREZ Members of the jury: Pr. LAURENT HOUSSIAU (President) Pr. PAOLA PALMERO Dr. CLAUDE ESTOURNES Dr. PHILIPPE AUBRY Pr. OLIVIER DEPARIS Dr. FRANCIS CAMBIER Dr. LAURENT BOILET (Co-supervisor) Pr. LUC HENRARD (Supervisor) Doctoral Thesis January 2018 Acknowledgments Je tiens tout d’abord à remercier la Région Wallonne (DG06) qui a financé ce projet dans le cadre du programme First DoCA (First Doctorat Centre Agréé, nº convention ECV320600FD017F/1217883) et les directeurs du BCRC pour avoir eu confiance en moi pour mener à bout ce projet. Mes remerciements vont ensuite à mon promoteur du BCRC, Laurent Boilet, pour être toujours là pour m’aider, pour ses conseils et son engagement. Il est aussi devenu un bon ami que j’espère toujours garder. Merci Laurent pour tout. Un grand merci aussi à mon promoteur de l’Université de Namur, Luc Henrard, pour avoir suivi mon travail si éloigné de ses thématiques habituelles, pour sa disponibilité et sa gentillesse. Je remercie également Philippe Aubry pour avoir suivi mon travail depuis le début, pour m’avoir aidé et encouragé et Jean-Pierre Erauw qui m’a aidé lors de mes doutes sur le SPS, pour les simulations et a pris le temps de relire certaines parties du manuscrit pendant son temps libre et m’a fait des remarques constructives et judicieuses. Mes remerciements vont aussi aux autres membres du comité d’accompagnement: Francis Cambier et Olivier Deparis pour avoir accepté de suivre ce projet, pour leur lecture attentive du manuscrit et leurs commentaires et corrections. Ma gratitude va également aux autres membres du jury qui ont accepté d’évaluer ce travail : Paola Palmero qui m’a accueillie chaleureusement au sein de son laboratoire à Turin, Claude Estournès qui m’a fait l’honneur d’assister à ma soutenance et, enfin, Laurent Houssiau qui a accepté d’assurer la présidence du jury. Un tout grand merci aussi à Védi Dupont, pour son assistance technique lors des essais SPS et sa bonne humeur. Ma gratitude va également à mes collègues, chercheurs, techniciens et personnels administratifs, lesquels m’ont aidée et accompagnée pendant ces quatre années et avec lesquels j’ai passé des bons moments. Por último, no puedo olvidar a mi familia y a Antonio, por su apoyo incondicional y sus consejos, ni a mis amigos, tanto de España como los que he encontrado en Mons, que me han animado, escuchado y soportado este tiempo, especialmente a Patri por estar siempre pendiente a pesar de la distancia. J’espère n’avoir oublié personne, mais si c’est le cas, ils connaissent ma petite tête. Merci à tous ceux qui ont participé, de près ou de loin, à l’avancée de ce projet. Table of contents Table of contents Abstract ............................................................................................................................ 5 List of symbols and abbreviations ..................................................................................... 7 List of publications and presentations ............................................................................... 9 Introduction ................................................................................................................... 11 Chapter I - Literature review ........................................................................................... 15 1.1. Transparent ceramics ........................................................................................... 17 1.1.1. Fundamental aspects and transparency conditions ............................................ 17 1.1.2. Production of transparent ceramics ..................................................................... 20 1.1.2.1. Influence of powder properties and powder conditioning ..................................... 21 1.1.2.2. Sintering of transparent ceramics ............................................................................ 22 1.2. Yttrium aluminium garnet .................................................................................... 35 1.2.1. Structure, properties and applications ................................................................. 35 1.2.2. Synthesis ................................................................................................................ 37 1.2.3. Transparent YAG ceramics .................................................................................... 39 1.3. Barium Titanate .................................................................................................... 41 1.3.1. Structure ................................................................................................................ 41 1.3.2. Properties and applications .................................................................................. 43 1.3.3. Effect of strontium substitution ........................................................................... 47 1.3.4. Transparent BT and BST ceramics......................................................................... 50 1.4. Conclusions .......................................................................................................... 52 Chapter II – Experimental procedures and finite element modelling ................................ 55 2.1. Powder conditioning ............................................................................................ 57 2.1.1. Dispersion .............................................................................................................. 57 2.1.2. Solvent removal..................................................................................................... 57 2.2. Sintering and post-treatments .............................................................................. 57 2.2.1. Spark Plasma Sintering .......................................................................................... 57 2.2.2. Hot Isostatic Pressing ............................................................................................ 58 2.3. Physico-chemical characterizations ....................................................................... 59 2.3.1. Granulometric measurements .............................................................................. 59 2.3.2. X-Ray Diffraction ................................................................................................... 59 1 Table of contents 2.3.3. Specific surface area .............................................................................................. 60 2.3.4. Trace-level elemental analysis .............................................................................. 60 2.3.5. Raman spectroscopy ............................................................................................. 60 2.3.6. TGA/DTA ................................................................................................................ 60 2.3.7. Archimedes’s method ........................................................................................... 60 2.3.8. Permittivity measurements .................................................................................. 61 2.4. Microstructural characterisation ........................................................................... 62 2.5. Optical characterisation ........................................................................................ 62 2.6. Finite Element Modelling to simulate temperature distribution in SPS .................. 64 Chapter III – Yttrium Aluminium Garnet .......................................................................... 67 3.1. YAG-S
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