{"id":2457,"date":"2026-01-24T07:40:32","date_gmt":"2026-01-24T06:40:32","guid":{"rendered":"https:\/\/www.nickelcasting.com\/?p=2457"},"modified":"2026-01-30T03:00:38","modified_gmt":"2026-01-30T02:00:38","slug":"alloy-20-vs-904l","status":"publish","type":"post","link":"https:\/\/www.nickelcasting.com\/ja\/alloy-20-vs-904l\/","title":{"rendered":"\u5408\u91d120\u3068904L\u306e\u6bd4\u8f03\uff1a\u8010\u786b\u9178\u6027"},"content":{"rendered":"

\u9ad8\u6027\u80fd\u30aa\u30fc\u30b9\u30c6\u30ca\u30a4\u30c8\u7cfb\u30b9\u30c6\u30f3\u30ec\u30b9\u92fc\u306e\u9818\u57df\u3067 \u306f\u3001Alloy 20 (UNS N08020)\u3068904L (UNS N08904)\u306e\u3069\u3061\u3089\u3092\u9078\u629e\u3059\u308b \u304b\u304c\u3001\u91cd\u8981\u306a\u7523\u696d\u6a5f\u5668\u306e\u5bff\u547d\u3092\u6c7a\u3081\u308b\u3053\u3068\u304c\u591a\u3044\u3002\u4e21\u5408\u91d1\u306f\u3001\u6a19\u6e96\u7684\u306a316L\u30b9\u30c6\u30f3\u30ec\u30b9\u92fc\u3068\u9ad8 \u4fa1\u306a\u30cb\u30c3\u30b1\u30eb\u57fa\u8d85\u5408\u91d1\u3068\u306e\u30ae\u30e3\u30c3\u30d7\u3092\u57cb\u3081\u308b\u305f \u3081\u306b\u8a2d\u8a08\u3055\u308c\u305f\u304c\u3001\u8010\u98df\u6027\u3001\u7279\u306b\u9178\u6027\u74b0\u5883\u306b\u304a\u3044\u3066 \u306f\u3001\u305d\u308c\u305e\u308c\u7570\u306a\u308b\u30cb\u30c3\u30c1\u3092\u5360\u3081\u3066\u3044\u308b\u3002.<\/p>\n

\"\"<\/p>\n

\u5408\u91d120\u3068904L\u306e\u6bd4\u8f03\uff1a\u5316\u5b66\u7684\u304a\u3088\u3073\u7269\u7406\u7684\u7279\u5fb4<\/h2>\n

Understanding the Alloy 20 vs 904L comparison begins with their chemical signatures. Alloy 20 is frequently classified as a “super-austenitic” stainless steel or a nickel alloy because of its high nickel content (approx. 35%). This high nickel concentration, combined with copper and molybdenum, provides exceptional resistance to sulfuric acid at various temperatures and concentrations.<\/p>\n

\u5bfe\u7167\u7684\u306b\u3001904L\u306f\u9ad8\u5408\u91d1\u30aa\u30fc\u30b9\u30c6\u30ca\u30a4\u30c8\u7cfb\u30b9\u30c6\u30f3 \u30ec\u30b9\u92fc\u3067\u3001\u30cb\u30c3\u30b1\u30eb\u542b\u6709\u91cf\u306f\u7d0425%\u3067\u3042\u308b\u3002\u5f37\u9084\u5143\u6027\u9178\u3078\u306e\u8010\u6027\u3092\u9ad8\u3081\u308b\u305f\u3081\u306b\u9285\u3082\u542b\u6709\u3057\u3066\u3044\u308b\u304c\u3001\u4e3b\u306b\u5e0c\u786b\u9178\u3084\u30ea\u30f3\u9178\u74b0\u5883\u4e0b\u3067\u306e\u5b54\u98df\u3084\u9699\u9593\u8150\u98df\u306b\u8010\u3048\u308b\u3088\u3046\u306b\u958b\u767a\u3055\u308c\u305f\u3002.<\/p>\n

\u6280\u8853\u4ed5\u69d8\u8868<\/h3>\n\n\n\n\n\n\n\n\n\n\n
\u30d7\u30ed\u30d1\u30c6\u30a3<\/td>\n\u5408\u91d120 (UNS N08020)<\/td>\n904L (uns N08904)<\/td>\n<\/tr>\n<\/thead>\n
\u30cb\u30c3\u30b1\u30eb\uff08Ni\uff09<\/td>\n32.5% - 35.0%<\/td>\n23.0% - 28.0%<\/td>\n<\/tr>\n
\u30af\u30ed\u30e0\uff08Cr\uff09<\/td>\n19.0% - 21.0%<\/td>\n19.0% - 23.0%<\/td>\n<\/tr>\n
\u30e2\u30ea\u30d6\u30c7\u30f3 (Mo)<\/td>\n2.0% - 3.0%<\/td>\n4.0% - 5.0%<\/td>\n<\/tr>\n
\u9285\uff08Cu\uff09<\/td>\n3.0% - 4.0%<\/td>\n1.0% - 2.0%<\/td>\n<\/tr>\n
PREN\u5024<\/td>\n~24 – 26<\/td>\n~34 – 36<\/td>\n<\/tr>\n
\u964d\u4f0f\u5f37\u5ea6<\/td>\n35,000 psi (241 MPa)<\/td>\n31,000 psi (215 MPa)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u5408\u91d120\u3068904L\u306e\u6bd4\u8f03\uff1a\u6b63\u3057\u3044\u7d20\u6750\u306e\u9078\u3073\u65b9<\/h2>\n

\u5408\u91d120\u3068904L\u306e\u6bd4\u8f03\uff1a\u3069\u306e\u3088\u3046\u306b\u9078\u629e\u3059\u308b\u304b\u3092\u6c7a\u5b9a\u3059\u308b\u969b\u3001\u7b2c\u4e00\u306e\u8981\u56e0\u306f\u8150\u98df\u5a92\u4f53\u306e\u7279\u5b9a\u306e\u6027\u8cea\u3067\u3042\u308b\u3002.<\/p>\n

    \n
  1. \n

    \u5869\u5316\u7269\u5bfe\u9178\u6fc3\u5ea6\uff1a\u9ad8\u6fc3\u5ea6\u306e\u5869\u5316\u7269\u3092\u4f7f\u7528\u3059\u308b\u7528\u9014\u3067\u3001\u5b54\u98df\u304c\u4e3b\u306a\u61f8\u5ff5\u4e8b\u9805\u3067\u3042\u308b\u5834\u5408\u306f\u3001\u30e2\u30ea\u30d6\u30c7\u30f3\u542b\u6709\u91cf\u304c\u9ad8\u304f\u3001\u8010\u5b54\u98df\u6027\u7b49\u4fa1\u6570\uff08PREN\uff09\u304c\u9ad8\u3044904L\u304c\u512a\u308c\u305f\u9078\u629e\u80a2\u3068\u306a\u308b\u3053\u3068\u304c\u591a\u3044\u3002.<\/p>\n<\/li>\n

  2. \n

    Sulfuric Acid Purity: Alloy 20 is the industry standard for “Sulfuric Acid Service.” It excels in 20% to 40% sulfuric acid concentrations where other steels fail. Its niobium (columbium) stabilization also prevents intergranular corrosion during welding.<\/p>\n<\/li>\n

  3. \n

    \u30b3\u30b9\u30c8\u52b9\u7387\uff1a\u4e00\u822c\u7684\u306b\u3001904L\u306f\u6c4e\u7528\u5316\u5b66\u85ac\u54c1\u306b\u5bfe\u3059 \u308b\u30b3\u30b9\u30c8\u52b9\u7387\u304c\u9ad8\u304f\u3001Alloy 20\u306f\u9178\u306e\u6cb8\u70b9\u304c\u9ad8 \u304f\u3001\u71b1\u4ea4\u63db\u5668\u7528\u30c1\u30e5\u30fc\u30d6\u306b\u7279\u5316\u3057\u305f\u6295\u8cc7\u3068\u306a\u308b\u3002.<\/p>\n<\/li>\n<\/ol>\n

    \"\"<\/h2>\n

    \u5408\u91d120\u3068904L\u306e\u6bd4\u8f03\uff1a\u5316\u5b66\u30d7\u30e9\u30f3\u30c8\u306e\u9078\u629e\u6226\u7565<\/h2>\n

    \u30a2\u30ed\u30a420\u3068904L\u306e\u5316\u5b66\u30d7\u30e9\u30f3\u30c8\u306e\u9078\u629e\u306b\u304a\u3044\u3066\u3001\u30a8\u30f3\u30b8\u30cb\u30a2\u306f\u30c8\u30fc\u30bf\u30eb\u30e9\u30a4\u30d5\u30b5\u30a4\u30af\u30eb\u30b3\u30b9\u30c8\u306b\u6ce8\u76ee\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u5316\u5b66\u51e6\u7406\u30d7\u30e9\u30f3\u30c8\u3067\u306f\u3001\u9ad8\u6e29\u306795%\u307e \u3067\u306e\u786b\u9178\u6fc3\u5ea6\u3092\u6271\u3046\u9178\u6d17\u30bf\u30f3\u30af\u3001\u6df7\u5408\u30bf \u30f3\u30af\u3001\u71b1\u4ea4\u63db\u5668\u306b\u306fAlloy 20\u304c\u597d\u307e\u308c\u3066\u3044 \u308b\u3002.<\/p>\n

    Conversely, 904L is the go-to for flue-gas desulfurization (FGD) systems, pharmaceutical manufacturing, and paper pulp processing. It provides a robust defense against “warm sea water” and brackish water, making it ideal for coastal chemical facilities where external salt spray adds an extra layer of corrosive stress to the piping.<\/p>\n

    \n

    \u95a2\u9023Q&A<\/h3>\n

    Q1: Alloy20\u306f\u6d77\u6c34\u306b\u4f7f\u7528\u3067\u304d\u307e\u3059\u304b\uff1fA1: \u8010\u98df\u6027\u306f\u305d\u3053\u305d\u3053\u3067\u3059\u304c\u3001\u4e00\u822c\u7684\u306b\u6d77\u6c34\u3084\u9ad8\u5869\u5316\u7269\u74b0\u5883\u3067\u306f904L\u306e\u65b9\u304cPREN\u304c\u9ad8\u304f\uff0834-36\uff09\u3001\u8010\u5b54\u98df\u6027\u306b\u512a\u308c\u3066\u3044\u307e\u3059\u3002.<\/p>\n

    Q2: Why is Alloy 20 called “The Carpenter 20” alloy? A2: It was originally developed by Carpenter Technology Corporation. Today, many manufacturers produce it under the UNS N08020 specification, but it remains the benchmark for sulfuric acid resistance.<\/p>\n

    Q3: \u5316\u5b66\u5de5\u5834\u3067\u306f\u3069\u3061\u3089\u306e\u5408\u91d1\u304c\u6eb6\u63a5\u3057\u3084\u3059\u3044\u3067\u3059\u304b\uff1fA3: \u3069\u3061\u3089\u3082TIG\u3084MIG\u306e\u3088\u3046\u306a\u4e00\u822c\u7684\u306a\u65b9\u6cd5\u3067\u826f\u597d\u306a \u6eb6\u63a5\u6027\u3092\u793a\u3057\u307e\u3059\u3002\u3057\u304b\u3057\u3001Alloy 20\u306f\u30cb\u30aa\u30d6\u3092\u5b89\u5b9a\u5316\u3055\u305b\u3066\u3044\u308b\u305f\u3081\u3001904L\u306b\u6bd4\u3079\u3066\u71b1\u5f71\u97ff\u90e8(HAZ)\u3067\u306e\u70ad\u5316\u7269\u306e\u6790\u51fa\u306b\u5bfe\u3059\u308b\u8010\u6027\u304c\u82e5\u5e72\u9ad8\u304f\u306a\u3063\u3066\u3044\u307e\u3059\u3002.<\/p>","protected":false},"excerpt":{"rendered":"

    In the realm of high-performance austenitic stainless steels, the choice between Alloy 20 (UNS N08020) and 904L (UNS N08904) often defines the longevity of critical industrial equipment. While both alloys were engineered to bridge the gap between standard 316L stainless steel and high-cost nickel-based superalloys, they occupy distinct niches in corrosion resistance, particularly in acidic environments. Alloy 20 vs 904L Comparison: Chemical and Physical Nuances Understanding the Alloy 20 vs 904L comparison begins with their chemical signatures. Alloy 20 is frequently classified as a “super-austenitic” stainless steel or a nickel alloy because of its high nickel content (approx. 35%). This high nickel concentration, combined with copper and molybdenum, provides exceptional […]<\/p>","protected":false},"author":1,"featured_media":2458,"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 center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center 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-2457","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"spectra_custom_meta":{"_edit_lock":["1769738438:1"],"_edit_last":["1"],"rank_math_seo_score":["69"],"rank_math_description":["A technical guide comparing Alloy 20 and 904L stainless steels. Explore chemical properties, sulfuric acid resistance, and chemical plant selection."],"rank_math_focus_keyword":["alloy 20 vs 904l"],"_thumbnail_id":["2458"],"_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"],"ilj_blacklistdefinition":["a:0:{}"],"ilj_linkdefinition":["a:1:{i:0;s:16:\"Alloy 20 vs 904L\";}"],"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;}"],"_uag_css_file_name":["uag-css-2457.css"],"_elementor_page_assets":["a:0:{}"]},"uagb_featured_image_src":{"full":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74.jpg",1200,670,false],"thumbnail":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74-150x150.jpg",150,150,true],"medium":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74-300x168.jpg",300,168,true],"medium_large":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74-768x429.jpg",768,429,true],"large":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74-1024x572.jpg",1024,572,true],"1536x1536":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74.jpg",1200,670,false],"2048x2048":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74.jpg",1200,670,false],"trp-custom-language-flag":["https:\/\/www.nickelcasting.com\/wp-content\/uploads\/2026\/01\/74-18x10.jpg",18,10,true]},"uagb_author_info":{"display_name":"nickel","author_link":"https:\/\/www.nickelcasting.com\/ja\/author\/nickel\/"},"uagb_comment_info":0,"uagb_excerpt":"In the realm of high-performance austenitic stainless steels, the choice between Alloy 20 (UNS N08020) and 904L (UNS N08904) often defines the longevity of critical industrial equipment. While both alloys were engineered to bridge the gap between standard 316L stainless steel and high-cost nickel-based superalloys, they occupy distinct niches in corrosion resistance, particularly in acidic…","_links":{"self":[{"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/posts\/2457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/comments?post=2457"}],"version-history":[{"count":1,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/posts\/2457\/revisions"}],"predecessor-version":[{"id":2460,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/posts\/2457\/revisions\/2460"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/media\/2458"}],"wp:attachment":[{"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/media?parent=2457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/categories?post=2457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nickelcasting.com\/ja\/wp-json\/wp\/v2\/tags?post=2457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}