{"id":2449,"date":"2026-01-23T10:08:45","date_gmt":"2026-01-23T09:08:45","guid":{"rendered":"https:\/\/www.nickelcasting.com\/?p=2449"},"modified":"2026-01-30T03:00:49","modified_gmt":"2026-01-30T02:00:49","slug":"alliage-20-vs-incoloy-825-une-comparaison-technique-pour-les-environnements-critiques","status":"publish","type":"post","link":"https:\/\/www.nickelcasting.com\/fr\/alliage-20-vs-incoloy-825-une-comparaison-technique-pour-les-environnements-critiques\/","title":{"rendered":"Alliage 20 vs Incoloy 825 : Une comparaison technique pour les environnements critiques"},"content":{"rendered":"<p>Le choix du bon mat\u00e9riau pour des applications industrielles hautement corrosives conduit souvent \u00e0 une comparaison entre deux alliages puissants de nickel-fer-chrome : l'alliage 20 (UNS N08020) et le nickel-fer-chrome. <a href=\"https:\/\/www.nickelcasting.com\/ko\/%eb%8b%88%ec%bc%88-%ed%95%a9%ea%b8%88\/%ec%9d%b8%ec%bd%94%eb%a1%9c%ec%9d%b4-%ea%b8%88%ec%86%8d-%ed%95%a9%ea%b8%88\/incoloy-825\/\">Incoloy 825<\/a> (UNS N08825). Bien que ces deux alliages soient con\u00e7us pour r\u00e9sister aux milieux agressifs, leurs nuances m\u00e9tallurgiques d\u00e9terminent leur ad\u00e9quation \u00e0 des processus chimiques sp\u00e9cifiques. Cet article explore les diff\u00e9rences techniques, les r\u00e9f\u00e9rences de performance et les crit\u00e8res de s\u00e9lection de ces alliages.<\/p>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter size-full wp-image-2454\" src=\"http:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72.jpg\" alt=\"\" width=\"1200\" height=\"670\" srcset=\"https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72.jpg 1200w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-300x168.jpg 300w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-1024x572.jpg 1024w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-768x429.jpg 768w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-18x10.jpg 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<h2 data-path-to-node=\"3\">Comparaison entre l'alliage 20 et l'Incoloy 825<\/h2>\n<p data-path-to-node=\"4\">D'un point de vue m\u00e9tallurgique, les deux mat\u00e9riaux sont des alliages \u201csuper-aust\u00e9nitiques\u201d ou \u00e0 forte teneur en nickel, con\u00e7us pour combler le foss\u00e9 entre les aciers inoxydables standard de la s\u00e9rie 300 et les superalliages \u00e0 base de nickel tr\u00e8s co\u00fbteux. Toutefois, ils se distinguent par leurs \u00e9l\u00e9ments stabilisateurs et leur teneur en nickel.<\/p>\n<p data-path-to-node=\"5\">L'alliage 20, souvent appel\u00e9 \u201cCarpenter 20\u201d, est stabilis\u00e9 avec du Niobium (Columbium). Cet ajout emp\u00eache la corrosion intergranulaire en inhibant la pr\u00e9cipitation du carbure pendant le soudage. En revanche, l'Incoloy 825 est stabilis\u00e9 avec du titane, qui remplit une fonction similaire mais se comporte diff\u00e9remment dans les environnements oxydants.<\/p>\n<h3 data-path-to-node=\"6\">Comparaison des propri\u00e9t\u00e9s chimiques et m\u00e9caniques<\/h3>\n<table data-path-to-node=\"7\">\n<thead>\n<tr>\n<td>Propri\u00e9t\u00e9<\/td>\n<td>Alliage 20 (UNS N08020)<\/td>\n<td>Incoloy 825 (UNS N08825)<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Nickel (Ni) %<\/td>\n<td>32.5 - 38.0<\/td>\n<td>38.0 - 46.0<\/td>\n<\/tr>\n<tr>\n<td>Chrome (Cr) %<\/td>\n<td>19.0 - 21.0<\/td>\n<td>19.5 - 23.5<\/td>\n<\/tr>\n<tr>\n<td>Cuivre (Cu) %<\/td>\n<td>3.0 - 4.0<\/td>\n<td>1.5 - 3.0<\/td>\n<\/tr>\n<tr>\n<td>Molybd\u00e8ne (Mo) %<\/td>\n<td>2.0 - 3.0<\/td>\n<td>2.5 - 3.5<\/td>\n<\/tr>\n<tr>\n<td>Stabilisateur<\/td>\n<td>Niobium (Nb)<\/td>\n<td>Titane (Ti)<\/td>\n<\/tr>\n<tr>\n<td>R\u00e9sistance \u00e0 la traction (ksi)<\/td>\n<td>80 min<\/td>\n<td>85 min<\/td>\n<\/tr>\n<tr>\n<td>Limite d'\u00e9lasticit\u00e9 (d\u00e9calage de 0,2%, ksi)<\/td>\n<td>35 min<\/td>\n<td>35 min<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Alors que l'Incoloy 825 pr\u00e9sente une teneur plus \u00e9lev\u00e9e en nickel, ce qui lui conf\u00e8re une r\u00e9sistance sup\u00e9rieure \u00e0 la fissuration par corrosion sous contrainte induite par les chlorures, l'Alliage 20 pr\u00e9sente une teneur plus \u00e9lev\u00e9e en cuivre, ce qui constitue le secret de ses performances l\u00e9gendaires dans les acides r\u00e9ducteurs.<\/p>\n<h2 data-path-to-node=\"10\">Alliage 20 ou Incoloy 825 : comment choisir ?<\/h2>\n<p data-path-to-node=\"11\">Le choix entre l'alliage 20 et l'Incoloy 825 se r\u00e9sume rarement \u00e0 la question de savoir lequel est \u201cmeilleur\u201d, mais plut\u00f4t lequel est \u201cadapt\u00e9\u201d aux caract\u00e9ristiques chimiques sp\u00e9cifiques de l'environnement.<\/p>\n<ol start=\"1\" data-path-to-node=\"12\">\n<li>\n<p data-path-to-node=\"12,0,0\">R\u00e9sistance aux chlorures : Si votre application implique des niveaux \u00e9lev\u00e9s de chlorures (comme l'eau de mer ou l'eau saum\u00e2tre) et que la corrosion par piq\u00fbres et par crevasses est une pr\u00e9occupation majeure, l'Incoloy 825 est g\u00e9n\u00e9ralement le choix le plus s\u00fbr. Sa teneur plus \u00e9lev\u00e9e en molybd\u00e8ne et en nickel lui conf\u00e8re un indice \u00e9quivalent de r\u00e9sistance aux piq\u00fbres (PREN) plus \u00e9lev\u00e9.<\/p>\n<\/li>\n<li>\n<p data-path-to-node=\"12,1,0\">Limites de temp\u00e9rature : L'Incoloy 825 est g\u00e9n\u00e9ralement con\u00e7u pour une utilisation jusqu'\u00e0 <span aria-hidden=\"true\">1000\u2218F<\/span> (<span aria-hidden=\"true\">540\u2218C<\/span>), bien que ses propri\u00e9t\u00e9s m\u00e9caniques restent stables \u00e0 des temp\u00e9ratures cryog\u00e9niques. L'alliage 20 est fr\u00e9quemment utilis\u00e9 dans des proc\u00e9d\u00e9s o\u00f9 les temp\u00e9ratures restent inf\u00e9rieures \u00e0 <span aria-hidden=\"true\">800\u2218F<\/span>.<\/p>\n<\/li>\n<li>\n<p data-path-to-node=\"12,2,0\">Rentabilit\u00e9 : Historiquement, l'alliage 20 a \u00e9t\u00e9 le choix le plus rentable pour les usines de traitement chimique qui se concentrent strictement sur l'acide sulfurique. Cependant, l'Incoloy 825 \u00e9tant plus largement utilis\u00e9 dans le secteur du p\u00e9trole et du gaz, la disponibilit\u00e9 mondiale peut parfois rendre le 825 plus accessible malgr\u00e9 sa teneur en nickel plus \u00e9lev\u00e9e.<\/p>\n<\/li>\n<\/ol>\n<h2 data-path-to-node=\"14\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-2455\" src=\"http:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73.jpg\" alt=\"\" width=\"1200\" height=\"670\" srcset=\"https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73.jpg 1200w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73-300x168.jpg 300w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73-1024x572.jpg 1024w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73-768x429.jpg 768w, https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/73-18x10.jpg 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/h2>\n<h2 data-path-to-node=\"14\">Alliage 20 vs 825 pour le service d'acide sulfurique<\/h2>\n<p data-path-to-node=\"15\">Acide sulfurique (<span aria-hidden=\"true\">H2SO4<\/span>) est le principal terrain d'action de ces deux alliages. L'alliage 20 a \u00e9t\u00e9 sp\u00e9cifiquement d\u00e9velopp\u00e9 pour l'acide sulfurique. Sa forte teneur en cuivre (<span aria-hidden=\"true\">3.0-4.0%<\/span>) lui permet de maintenir un film protecteur en pr\u00e9sence de cet acide r\u00e9ducteur, m\u00eame \u00e0 des concentrations qui d\u00e9truiraient rapidement l'acier inoxydable 316L.<\/p>\n<ul data-path-to-node=\"16\">\n<li>\n<p data-path-to-node=\"16,0,0\">Performance de l'alliage 20 : Il s'agit souvent de l\u201c\u201d\u00e9talon-or\" pour les <span aria-hidden=\"true\">20%<\/span> \u00e0 <span aria-hidden=\"true\">40%<\/span> l'acide sulfurique \u00e0 des temp\u00e9ratures \u00e9lev\u00e9es. Il pr\u00e9sente une excellente r\u00e9sistance dans toute la gamme de concentrations jusqu'\u00e0 environ <span aria-hidden=\"true\">150\u2218F<\/span> (<span aria-hidden=\"true\">65\u2218C<\/span>).<\/p>\n<\/li>\n<li>\n<p data-path-to-node=\"16,1,0\">Performance de l'Incoloy 825 : Bien que le 825 soit \u00e9galement excellent en <span aria-hidden=\"true\">H2SO4<\/span>, Il est souvent pr\u00e9f\u00e9rable que l'acide soit \u201cmixte\u201d, c'est-\u00e0-dire qu'il contienne des sels oxydants (comme des ions ferriques ou cuivriques) ou des chlorures. Dans l'acide sulfurique hautement concentr\u00e9 et \u00e0 haute temp\u00e9rature (<span aria-hidden=\"true\">&gt;90%<\/span>), les deux alliages commencent \u00e0 atteindre leurs limites, n\u00e9cessitant souvent des mat\u00e9riaux plus sp\u00e9cialis\u00e9s comme l'Hastelloy\u00ae C276.<\/p>\n<\/li>\n<\/ul>\n<p data-path-to-node=\"17\">En r\u00e9sum\u00e9, pour les boucles d'acide sulfurique pur et \u201cpropre\u201d, l'alliage 20 offre la long\u00e9vit\u00e9 la plus fiable. Pour les flux chimiques complexes et contamin\u00e9s, l'Incoloy 825 offre une protection plus large.<\/p>\n<hr data-path-to-node=\"18\" \/>\n<h3 data-path-to-node=\"19\">Questions et r\u00e9ponses connexes<\/h3>\n<p data-path-to-node=\"20\">Q1 : L'alliage 20 est-il plus r\u00e9sistant \u00e0 la corrosion fissurante sous contrainte (SCC) que l'Incoloy 825 ? En g\u00e9n\u00e9ral, non. Bien que l'alliage 20 soit r\u00e9sistant \u00e0 la fissuration par corrosion sous contrainte, la teneur plus \u00e9lev\u00e9e en nickel de l'Incoloy 825 (<span aria-hidden=\"true\">38-46%<\/span>) offre une d\u00e9fense l\u00e9g\u00e8rement plus robuste contre la fissuration par corrosion sous contrainte induite par les chlorures dans les environnements extr\u00eames.<\/p>\n<p data-path-to-node=\"21\">Q2 : L'alliage 20 peut-il \u00eatre utilis\u00e9 dans l'acide nitrique ? Oui. En raison de sa teneur en chrome, l'alliage 20 pr\u00e9sente une bonne r\u00e9sistance aux acides oxydants tels que l'acide nitrique. Cependant, si l'environnement est strictement oxydant, l'Incoloy 825 ou m\u00eame l'Alliage 600 peuvent \u00eatre \u00e9valu\u00e9s en fonction de la concentration et de la temp\u00e9rature.<\/p>\n<p data-path-to-node=\"22\">Q3 : Quel est l'alliage le plus facile \u00e0 souder ? Les deux alliages ont une excellente soudabilit\u00e9. La stabilisation au niobium de l'alliage 20 le rend tr\u00e8s r\u00e9sistant \u00e0 la corrosion intergranulaire dans la zone affect\u00e9e thermiquement (ZAT). L'utilisation du bon m\u00e9tal d'apport (par exemple, ER320LR pour l'alliage 20 et ERNiCrMo-3 pour le 825) est essentielle pour maintenir la r\u00e9sistance \u00e0 la corrosion.<\/p>","protected":false},"excerpt":{"rendered":"<p>Le choix du bon mat\u00e9riau pour les applications industrielles hautement corrosives conduit souvent \u00e0 une comparaison entre deux alliages puissants de nickel, de fer et de chrome, l'alliage 20 (UNS N08020) et l'Incoloy 825 (UNS N08825) : l'alliage 20 (UNS N08020) et l'Incoloy 825 (UNS N08825). Bien que ces deux alliages soient con\u00e7us pour r\u00e9sister aux milieux agressifs, leurs nuances m\u00e9tallurgiques d\u00e9terminent leur ad\u00e9quation \u00e0 des processus chimiques sp\u00e9cifiques. Cet article explore les diff\u00e9rences techniques, les r\u00e9f\u00e9rences de performance et [...]<\/p>","protected":false},"author":1,"featured_media":2454,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center 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center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[3],"tags":[],"class_list":["post-2449","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"spectra_custom_meta":{"_edit_lock":["1769738307:1"],"rank_math_seo_score":["64"],"_edit_last":["1"],"_wp_page_template":["default"],"rank_math_internal_links_processed":["1"],"site-sidebar-layout":["default"],"ast-site-content-layout":["default"],"site-content-style":["default"],"site-sidebar-style":["default"],"theme-transparent-header-meta":["default"],"rank_math_description":["Technical guide comparing Alloy 20 and Incoloy 825 properties, chemical resistance, and selection criteria for sulfuric acid and chloride environments."],"rank_math_focus_keyword":["alloy 20 vs incoloy 825"],"_thumbnail_id":["2454"],"_wp_old_slug":["alloy-20-vs-incoloy-825"],"ilj_blacklistdefinition":["a:0:{}"],"ilj_linkdefinition":["a:1:{i:0;s:23:\"Alloy 20 vs Incoloy 825\";}"],"astra-migrate-meta-layouts":["set"],"_uag_page_assets":["a:9:{s:3:\"css\";s:263:\".uag-blocks-common-selector{z-index:var(--z-index-desktop) !important}@media (max-width: 976px){.uag-blocks-common-selector{z-index:var(--z-index-tablet) !important}}@media (max-width: 767px){.uag-blocks-common-selector{z-index:var(--z-index-mobile) !important}}\n\";s:2:\"js\";s:0:\"\";s:18:\"current_block_list\";a:8:{i:0;s:11:\"core\/search\";i:1;s:10:\"core\/group\";i:2;s:12:\"core\/heading\";i:3;s:17:\"core\/latest-posts\";i:4;s:20:\"core\/latest-comments\";i:5;s:13:\"core\/archives\";i:6;s:15:\"core\/categories\";i:7;s:10:\"core\/image\";}s:8:\"uag_flag\";b:0;s:11:\"uag_version\";s:10:\"1776556632\";s:6:\"gfonts\";a:0:{}s:10:\"gfonts_url\";s:0:\"\";s:12:\"gfonts_files\";a:0:{}s:14:\"uag_faq_layout\";b:0;}"],"_elementor_page_assets":["a:0:{}"],"_uag_css_file_name":["uag-css-2449.css"]},"uagb_featured_image_src":{"full":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72.jpg",1200,670,false],"thumbnail":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-150x150.jpg",150,150,true],"medium":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-300x168.jpg",300,168,true],"medium_large":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-768x429.jpg",768,429,true],"large":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-1024x572.jpg",1024,572,true],"1536x1536":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72.jpg",1200,670,false],"2048x2048":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72.jpg",1200,670,false],"trp-custom-language-flag":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/72-18x10.jpg",18,10,true]},"uagb_author_info":{"display_name":"nickel","author_link":"https:\/\/www.nickelcasting.com\/fr\/author\/nickel\/"},"uagb_comment_info":0,"uagb_excerpt":"Selecting the right material for highly corrosive industrial applications often leads to a comparison between two powerhouse nickel-iron-chromium alloys: Alloy 20 (UNS N08020) and Incoloy 825 (UNS N08825). While both are engineered to withstand aggressive media, their metallurgical nuances dictate their suitability for specific chemical processes. This article explores the technical differences, performance benchmarks, and\u2026","_links":{"self":[{"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/posts\/2449","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/comments?post=2449"}],"version-history":[{"count":2,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/posts\/2449\/revisions"}],"predecessor-version":[{"id":2456,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/posts\/2449\/revisions\/2456"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/media\/2454"}],"wp:attachment":[{"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/media?parent=2449"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/categories?post=2449"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nickelcasting.com\/fr\/wp-json\/wp\/v2\/tags?post=2449"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}