{"id":158,"date":"2025-10-15T08:55:18","date_gmt":"2025-10-15T08:55:18","guid":{"rendered":"https:\/\/norkeceramics.com\/?p=158"},"modified":"2025-10-16T07:25:36","modified_gmt":"2025-10-16T07:25:36","slug":"ceramique-dalumine","status":"publish","type":"post","link":"https:\/\/norkeceramics.com\/fr\/ceramique-dalumine\/","title":{"rendered":"C\u00e9ramique \u00e0 base d'alumine"},"content":{"rendered":"<p>La c\u00e9ramique d&#039;alumine est un mat\u00e9riau c\u00e9ramique haute performance compos\u00e9 principalement d&#039;alumine \u03b1 (\u03b1-Al\u2082O\u2083) comme phase cristalline principale. Gr\u00e2ce \u00e0 ses propri\u00e9t\u00e9s physiques, chimiques et m\u00e9caniques exceptionnelles, elle est largement utilis\u00e9e dans les secteurs industriel, \u00e9lectronique, m\u00e9dical et autres.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Processus de pr\u00e9paration<\/h2>\n\n\n\n<p>1. Pr\u00e9paration des mati\u00e8res premi\u00e8res : Purification de la bauxite ou synth\u00e8se chimique pour produire de la poudre d&#039;alumine de haute puret\u00e9.<\/p>\n\n\n\n<p>2. Formation :<\/p>\n\n\n\n<p>Pressage \u00e0 sec (formes simples)<\/p>\n\n\n\n<p>Coulage en barbotine (formes complexes)<\/p>\n\n\n\n<p>Pressage isostatique (composants haute performance)<\/p>\n\n\n\n<p>3. Frittage : Densification \u00e0 haute temp\u00e9rature (1600 \u00b0C\u20131800 \u00b0C) par frittage atmosph\u00e9rique ou par pressage \u00e0 chaud.<\/p>\n\n\n\n<p>4. Post-traitement : Rectification et polissage de pr\u00e9cision (co\u00fbts de traitement \u00e9lev\u00e9s en raison de l&#039;extr\u00eame duret\u00e9).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Classification (selon la teneur en Al\u2082O\u2083)<\/h2>\n\n\n\n<p>C\u00e9ramiques d&#039;alumine standard : 75%\u201395% Al\u2082O\u2083, utilis\u00e9es pour les composants r\u00e9sistants \u00e0 la corrosion et \u00e0 l&#039;usure.<\/p>\n\n\n\n<p>C\u00e9ramiques d&#039;alumine de haute puret\u00e9 (\u226599%) : Appliqu\u00e9es en \u00e9lectronique et en biom\u00e9decine, par exemple, substrats isolants, articulations artificielles.<\/p>\n\n\n\n<p>C\u00e9ramiques d&#039;alumine transparentes : puret\u00e9 &gt;99,9%, utilis\u00e9es dans les lampes \u00e0 sodium haute pression et les fen\u00eatres infrarouges.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Avantages et inconv\u00e9nients<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Avantages :<\/h3>\n\n\n\n<p>Propri\u00e9t\u00e9s globales \u00e9quilibr\u00e9es (duret\u00e9, r\u00e9sistance \u00e0 la temp\u00e9rature, isolation).<\/p>\n\n\n\n<p>Abondance des sources de mati\u00e8res premi\u00e8res et co\u00fbt relativement faible (compar\u00e9 au nitrure de silicium, au carbure de silicium, etc.).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Inconv\u00e9nients :<\/h3>\n\n\n\n<p>Fragilit\u00e9 \u00e9lev\u00e9e et faible r\u00e9sistance aux chocs thermiques (peut \u00eatre am\u00e9lior\u00e9e par modification du composite).<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><strong>L&#039;usinage de haute pr\u00e9cision est difficile \u00e0 r\u00e9aliser. Les c\u00e9ramiques d&#039;alumine, qui offrent un bon compromis entre co\u00fbt et performance, figurent parmi les c\u00e9ramiques structurales les plus utilis\u00e9es. Elles pr\u00e9sentent un fort potentiel de croissance dans des domaines \u00e9mergents tels que les \u00e9nergies nouvelles et les semi-conducteurs.<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Param\u00e8tre<\/td><td>Valeur typique<\/td><td>Unit\u00e9<\/td><td>Remarques<\/td><\/tr><tr><td>Puret\u00e9<\/td><td>92%, 95%, 96%, 99%, 99.5%, 99.9%<\/td><td>%<\/td><td>Une puret\u00e9 plus \u00e9lev\u00e9e donne g\u00e9n\u00e9ralement de meilleures performances.<\/td><\/tr><tr><td>Densit\u00e9<\/td><td>3.6 3.98<\/td><td>g\/cm\u00b3<\/td><td>La puret\u00e9 99% est atteinte<\/td><\/tr><tr><td>R\u00e9sistance \u00e0 la flexion<\/td><td>300 400 (96%) \/ 350 450 (99%)<\/td><td>MPa<\/td><td>Affect\u00e9 par le processus de frittage<\/td><\/tr><tr><td>R\u00e9sistance \u00e0 la compression<\/td><td>2000 3000<\/td><td>MPa<\/td><td>Mat\u00e9riau \u00e0 haute duret\u00e9<\/td><\/tr><tr><td>Module de Young<\/td><td>300 380<\/td><td>GPa<\/td><td>Haute rigidit\u00e9<\/td><\/tr><tr><td>Duret\u00e9 Vickers (HV)<\/td><td>1500 1800<\/td><td>kgf\/mm\u00b2<\/td><td>haute r\u00e9sistance \u00e0 l&#039;usure<\/td><\/tr><tr><td>R\u00e9sistance \u00e0 la rupture (KIC)<\/td><td>3.5 4.5<\/td><td>MPa\u00b7m\u00b9\/\u00b2<\/td><td>Mat\u00e9riau relativement fragile<\/td><\/tr><tr><td>Coefficient de dilatation thermique<\/td><td>7 8 (20-1000\u00b0C)<\/td><td>\u00d710\u207b\u2076\/K<\/td><td>D\u00e9pendant de la temp\u00e9rature<\/td><\/tr><tr><td>Conductivit\u00e9 thermique<\/td><td>20 30 (25\u00b0C)<\/td><td>W\/(m\u00b7K)<\/td><td>Sup\u00e9rieure \u00e0 la plupart des c\u00e9ramiques<\/td><\/tr><tr><td>temp\u00e9rature de fonctionnement maximale<\/td><td>1500 1700<\/td><td>\u00b0C<\/td><td>En conditions \u00e0 vide<\/td><\/tr><tr><td>Constante di\u00e9lectrique (1 MHz)<\/td><td>9 10<\/td><td>-<\/td><td>Couramment utilis\u00e9 dans l&#039;emballage \u00e9lectronique<\/td><\/tr><tr><td>R\u00e9sistivit\u00e9 volumique (20\u00b0C)<\/td><td>&gt;10\u00b9\u2074<\/td><td>\u03a9\u00b7cm<\/td><td>Excellentes propri\u00e9t\u00e9s d&#039;isolation<\/td><\/tr><tr><td>rigidit\u00e9 di\u00e9lectrique<\/td><td>10 15<\/td><td>kV\/mm<\/td><td>Applications d&#039;isolation haute tension<\/td><\/tr><\/tbody><\/table><\/figure>","protected":false},"excerpt":{"rendered":"<p>Alumina ceramic is a high-performance ceramic material primarily composed of \u03b1-alumina (\u03b1-Al\u2082O\u2083) as its main crystalline phase. Due to its outstanding physical, chemical, and mechanical properties, it is widely used in industrial, electronic, medical, and other fields. Preparation Process 1. Raw Material Preparation: Purification of bauxite or chemical synthesis to produce high-purity alumina powder. 2. [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,7],"tags":[],"class_list":["post-158","post","type-post","status-publish","format-standard","hentry","category-products","category-alumina-ceramics"],"_links":{"self":[{"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/posts\/158","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/comments?post=158"}],"version-history":[{"count":4,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/posts\/158\/revisions"}],"predecessor-version":[{"id":167,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/posts\/158\/revisions\/167"}],"wp:attachment":[{"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/media?parent=158"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/categories?post=158"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/norkeceramics.com\/fr\/wp-json\/wp\/v2\/tags?post=158"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}