{"id":1551,"date":"2026-01-14T12:34:22","date_gmt":"2026-01-14T05:34:22","guid":{"rendered":"https:\/\/inoxcuongthinh.com\/co-che-chong-gi-inox-bi-mat-lop-mang-crom-thu-dong\/"},"modified":"2026-01-14T12:34:22","modified_gmt":"2026-01-14T05:34:22","slug":"co-che-chong-gi-inox-bi-mat-lop-mang-crom-thu-dong","status":"publish","type":"post","link":"https:\/\/inoxcuongthinh.com\/co-che-chong-gi-inox-bi-mat-lop-mang-crom-thu-dong\/","title":{"rendered":"C\u01a1 ch\u1ebf ch\u1ed1ng g\u1ec9 inox: b\u00ed m\u1eadt l\u1edbp m\u00e0ng crom th\u1ee5 \u0111\u1ed9ng"},"content":{"rendered":"<div class=\"custom-toc\">\n<h3>N\u1ed9i dung ch\u00ednh<\/h3>\n<ul>\n<li><a href=\"#toc-0-lop-mang-crom-thu-dong-la-gi\">L\u1edbp m\u00e0ng crom th\u1ee5 \u0111\u1ed9ng l\u00e0 g\u00ec?<\/a><\/li>\n<li><a href=\"#toc-1-hoa-hoc-va-dien-hoa-cua-tinh-thu-dong\">H\u00f3a h\u1ecdc v\u00e0 \u0111i\u1ec7n h\u00f3a c\u1ee7a t\u00ednh th\u1ee5 \u0111\u1ed9ng<\/a><\/li>\n<li><a href=\"#toc-2-vi-sao-105-cr-la-nguong-inox\">V\u00ec sao \u226510,5% Cr l\u00e0 \u201cng\u01b0\u1ee1ng\u201d inox?<\/a><\/li>\n<li><a href=\"#toc-3-an-mon-cuc-bo-ke-thu-cua-lop-thu-dong\">\u0102n m\u00f2n c\u1ee5c b\u1ed9: k\u1ebb th\u00f9 c\u1ee7a l\u1edbp th\u1ee5 \u0111\u1ed9ng<\/a><\/li>\n<li><a href=\"#toc-4-pren-chi-so-du-bao-chong-an-mon-lo\">PREN: ch\u1ec9 s\u1ed1 d\u1ef1 b\u00e1o ch\u1ed1ng \u0103n m\u00f2n l\u1ed7<\/a><\/li>\n<li><a href=\"#toc-5-anh-huong-moi-truong-dien-hinh-tai-viet-nam\">\u1ea2nh h\u01b0\u1edfng m\u00f4i tr\u01b0\u1eddng \u0111i\u1ec3n h\u00ecnh t\u1ea1i Vi\u1ec7t Nam<\/a><\/li>\n<li><a href=\"#toc-6-xu-ly-be-mat-de-duy-tri-tinh-thu-dong\">X\u1eed l\u00fd b\u1ec1 m\u1eb7t \u0111\u1ec3 duy tr\u00ec t\u00ednh th\u1ee5 \u0111\u1ed9ng<\/a><\/li>\n<li><a href=\"#toc-7-thiet-ke-chong-an-mon-quy-tac-thuc-tien\">Thi\u1ebft k\u1ebf ch\u1ed1ng \u0103n m\u00f2n: quy t\u1eafc th\u1ef1c ti\u1ec5n<\/a><\/li>\n<li><a href=\"#toc-8-304-316-201-430-duplex-chon-mac-nao\">304, 316, 201, 430, duplex: ch\u1ecdn m\u00e1c n\u00e0o?<\/a><\/li>\n<li><a href=\"#toc-9-nhan-biet-va-xu-ly-o-tra-so-voi-gi-that\">Nh\u1eadn bi\u1ebft v\u00e0 x\u1eed l\u00fd \u201c\u1ed1 tr\u00e0\u201d so v\u1edbi g\u1ec9 th\u1eadt<\/a><\/li>\n<li><a href=\"#toc-10-kiem-tra-va-tieu-chuan-lien-quan\">Ki\u1ec3m tra v\u00e0 ti\u00eau chu\u1ea9n li\u00ean quan<\/a><\/li>\n<li><a href=\"#toc-11-vi-du-ung-dung-nhanh\">V\u00ed d\u1ee5 \u1ee9ng d\u1ee5ng nhanh<\/a><\/li>\n<li><a href=\"#toc-12-tai-lieu-tham-khao\">T\u00e0i li\u1ec7u tham kh\u1ea3o<\/a><\/li>\n<li><a href=\"#toc-13-ket-luan\">K\u1ebft lu\u1eadn<\/a><\/li>\n<\/ul>\n<\/div>\n<p>Inox ch\u1ed1ng g\u1ec9 kh\u00f4ng ph\u1ea3i v\u00ec \u201ckh\u00f4ng c\u00f3 s\u1eaft\u201d, m\u00e0 nh\u1edd m\u1ed9t l\u1edbp m\u00e0ng crom th\u1ee5 \u0111\u1ed9ng c\u1ef1c m\u1ecfng, b\u1ec1n v\u00e0 t\u1ef1 t\u00e1i t\u1ea1o. Hi\u1ec3u c\u01a1 ch\u1ebf n\u00e0y l\u00e0 n\u1ec1n t\u1ea3ng \u0111\u1ec3 ch\u1ecdn m\u00e1c inox ph\u00f9 h\u1ee3p (304, 316, 201, 430, duplex), thi\u1ebft k\u1ebf ch\u1ed1ng \u0103n m\u00f2n, x\u1eed l\u00fd b\u1ec1 m\u1eb7t sau h\u00e0n v\u00e0 b\u1ea3o tr\u00ec \u0111\u00fang, \u0111\u1eb7c bi\u1ec7t trong m\u00f4i tr\u01b0\u1eddng Vi\u1ec7t Nam c\u00f3 h\u01a1i \u1ea9m v\u00e0 clorua cao.<\/p>\n<h2 id=\"toc-0-lop-mang-crom-thu-dong-la-gi\">L\u1edbp m\u00e0ng crom th\u1ee5 \u0111\u1ed9ng l\u00e0 g\u00ec?<\/h2>\n<p>&#8211; B\u1ea3n ch\u1ea5t: Khi h\u00e0m l\u01b0\u1ee3ng Cr trong th\u00e9p \u226510,5%, b\u1ec1 m\u1eb7t ti\u1ebfp x\u00fac v\u1edbi oxy s\u1ebd h\u00ecnh th\u00e0nh m\u1ed9t l\u1edbp oxit crom gi\u00e0u Cr (ch\u1ee7 y\u1ebfu Cr2O3 k\u00e8m hydroxide\/oxyhydroxide) d\u00e0y kho\u1ea3ng 1\u20133 nm. L\u1edbp m\u00e0ng n\u00e0y ng\u0103n trao \u0111\u1ed5i \u0111i\u1ec7n t\u1eed\/ion, c\u1eaft \u0111\u1ee9t chu\u1ed7i ph\u1ea3n \u1ee9ng oxy h\u00f3a s\u1eaft n\u00ean th\u00e9p kh\u00f4ng b\u1ecb g\u1ec9 \u0111\u1ecf.<br \/>\n&#8211; T\u1ef1 ph\u1ee5c h\u1ed3i: N\u1ebfu b\u1ecb x\u01b0\u1edbc nh\u1eb9, ch\u1ec9 c\u1ea7n c\u00f3 oxy v\u00e0 \u0111\u1ed9 \u1ea9m, l\u1edbp m\u00e0ng t\u00e1i sinh trong v\u00e0i gi\u00e2y \u0111\u1ebfn v\u00e0i ph\u00fat. \u0110\u00e2y l\u00e0 kh\u00e1c bi\u1ec7t c\u1ed1t l\u00f5i so v\u1edbi s\u01a1n ph\u1ee7: l\u1edbp th\u1ee5 \u0111\u1ed9ng l\u00e0 \u201ct\u1ef1 ch\u1eefa l\u00e0nh\u201d.<br \/>\n&#8211; \u0110i\u1ec1u ki\u1ec7n t\u1ed3n t\u1ea1i: C\u1ea7n m\u00f4i tr\u01b0\u1eddng c\u00f3 oxy h\u00f2a tan. Trong khe h\u1edf k\u00edn, n\u01b0\u1edbc \u0111\u1ecdng thi\u1ebfu oxy, l\u1edbp th\u1ee5 \u0111\u1ed9ng suy y\u1ebfu v\u00e0 d\u1ec5 b\u1ecb ph\u00e1 v\u1ee1.<\/p>\n<h2 id=\"toc-1-hoa-hoc-va-dien-hoa-cua-tinh-thu-dong\">H\u00f3a h\u1ecdc v\u00e0 \u0111i\u1ec7n h\u00f3a c\u1ee7a t\u00ednh th\u1ee5 \u0111\u1ed9ng<\/h2>\n<p>&#8211; M\u00e0ng hai l\u1edbp: L\u1edbp trong gi\u00e0u Cr2O3 \u0111\u1eb7c s\u00edt; l\u1edbp ngo\u00e0i hydrat h\u00f3a c\u00f3 l\u1eabn oxit s\u1eaft. Th\u00e0nh ph\u1ea7n v\u00e0 \u0111\u1ed9 d\u00e0y ph\u1ee5 thu\u1ed9c pH, th\u1ebf \u0111i\u1ec7n c\u1ef1c v\u00e0 h\u1ee3p kim h\u00f3a.<br \/>\n&#8211; Ng\u01b0\u1ee1ng ph\u00e1 v\u1ee1 v\u00e0 t\u00e1i th\u1ee5 \u0111\u1ed9ng:<br \/>\n  &#8211; Th\u1ebf ph\u00e1 m\u00e0ng (Epit): khi v\u01b0\u1ee3t ng\u01b0\u1ee1ng trong m\u00f4i tr\u01b0\u1eddng ch\u1ee9a Cl\u2212, x\u1ea3y ra \u0103n m\u00f2n c\u1ee5c b\u1ed9 (\u0111i\u1ec3n h\u00ecnh l\u00e0 \u0103n m\u00f2n l\u1ed7). V\u1edbi 304 trong dung d\u1ecbch NaCl, Epit th\u1ea5p h\u01a1n 316 do thi\u1ebfu Mo.<br \/>\n  &#8211; Th\u1ebf t\u00e1i th\u1ee5 \u0111\u1ed9ng (Erp): sau khi r\u1eeda s\u1ea1ch ion Cl\u2212 v\u00e0 c\u00f3 oxy, m\u00e0ng c\u00f3 th\u1ec3 t\u00e1i t\u1ea1o n\u1ebfu th\u1ebf tr\u1edf v\u1ec1 v\u00f9ng th\u1ee5 \u0111\u1ed9ng.<br \/>\n&#8211; Vai tr\u00f2 nguy\u00ean t\u1ed1 h\u1ee3p kim:<br \/>\n  &#8211; Cr: t\u1ea1o\/\u1ed5n \u0111\u1ecbnh m\u00e0ng th\u1ee5 \u0111\u1ed9ng. Ng\u01b0\u1ee1ng ~10,5% l\u00e0 \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 \u0111\u01b0\u1ee3c coi l\u00e0 \u201cstainless\u201d.<br \/>\n  &#8211; Mo: t\u0103ng kh\u00e1ng \u0103n m\u00f2n l\u1ed7\/khe b\u1eb1ng c\u00e1ch \u1ee9c ch\u1ebf h\u00f2a tan an\u1ed1t trong h\u1ed1 \u0103n m\u00f2n v\u00e0 \u0111\u1ea9y Erp l\u00ean cao.<br \/>\n  &#8211; N: t\u0103ng kh\u00e1ng khe, c\u1ea3i thi\u1ec7n t\u00e1i th\u1ee5 \u0111\u1ed9ng; \u0111\u1eb7c bi\u1ec7t hi\u1ec7u qu\u1ea3 trong th\u00e9p duplex\/austenitic N cao.<br \/>\n  &#8211; Ni: \u1ed5n \u0111\u1ecbnh t\u1ed5 ch\u1ee9c austenit (t\u0103ng d\u1ebbo, b\u1ec1n), gi\u00e1n ti\u1ebfp gi\u00fap m\u00e0ng \u1ed5n \u0111\u1ecbnh trong nhi\u1ec1u m\u00f4i tr\u01b0\u1eddng axit oxi h\u00f3a.<\/p>\n<h2 id=\"toc-2-vi-sao-105-cr-la-nguong-inox\">V\u00ec sao \u226510,5% Cr l\u00e0 \u201cng\u01b0\u1ee1ng\u201d inox?<\/h2>\n<p>\u1ede h\u00e0m l\u01b0\u1ee3ng n\u00e0y, t\u1ed1c \u0111\u1ed9 h\u00ecnh th\u00e0nh Cr2O3 v\u01b0\u1ee3t t\u1ed1c \u0111\u1ed9 h\u00f2a tan, t\u1ea1o m\u1ed9t m\u00e0ng li\u00ean t\u1ee5c che ph\u1ee7 b\u1ec1 m\u1eb7t. Th\u00eam Cr l\u00e0m gi\u00e0u Cr trong m\u00e0ng, gi\u1ea3m khuy\u1ebft t\u1eadt, t\u0103ng \u0111\u1ed9 b\u1ec1n \u0111i\u1ec7n h\u00f3a. Tuy nhi\u00ean, ch\u1ec9 Cr th\u00f4i ch\u01b0a \u0111\u1ee7 cho m\u00f4i tr\u01b0\u1eddng clorua kh\u1eafc nghi\u1ec7t; c\u1ea7n Mo v\u00e0\/ho\u1eb7c N \u0111\u1ec3 ch\u1ed1ng \u0103n m\u00f2n c\u1ee5c b\u1ed9 t\u1ed1t h\u01a1n.<\/p>\n<h2 id=\"toc-3-an-mon-cuc-bo-ke-thu-cua-lop-thu-dong\">\u0102n m\u00f2n c\u1ee5c b\u1ed9: k\u1ebb th\u00f9 c\u1ee7a l\u1edbp th\u1ee5 \u0111\u1ed9ng<\/h2>\n<h3>\u0102n m\u00f2n l\u1ed7 (pitting)<\/h3>\n<p>&#8211; T\u00e1c nh\u00e2n: ion Cl\u2212; nhi\u1ec7t \u0111\u1ed9 c\u00e0ng cao c\u00e0ng nguy hi\u1ec3m. Nhi\u1ec5m mu\u1ed1i bi\u1ec3n, n\u01b0\u1edbc b\u1eafn s\u00f3ng, ch\u1ea5t t\u1ea9y c\u00f3 clorua \u0111\u1ec1u l\u00e0m t\u0103ng r\u1ee7i ro.<br \/>\n&#8211; Nhi\u1ec7t \u0111\u1ed9 kh\u1edfi ph\u00e1t \u0103n m\u00f2n l\u1ed7 (CPT) tham kh\u1ea3o trong dung d\u1ecbch clorua ti\u00eau chu\u1ea9n:<br \/>\n  &#8211; 304: kho\u1ea3ng 10\u201320\u00b0C<br \/>\n  &#8211; 316\/316L (2\u20132,5% Mo): kho\u1ea3ng 25\u201335\u00b0C<br \/>\n  &#8211; 2205 duplex: kho\u1ea3ng 50\u201360\u00b0C<br \/>\n  (Gi\u00e1 tr\u1ecb thay \u0111\u1ed5i theo n\u1ed3ng \u0111\u1ed9, pH, b\u1ec1 m\u1eb7t, ti\u00eau chu\u1ea9n th\u1eed; ch\u1ec9 d\u00f9ng \u0111\u1ec3 \u0111\u1ecbnh h\u01b0\u1edbng.)<\/p>\n<h3>\u0102n m\u00f2n khe (crevice)<\/h3>\n<p>&#8211; Xu\u1ea5t hi\u1ec7n \u1edf bulong-kh\u1edbp, gio\u0103ng, gh\u00e9p g\u1ed1i. Trong khe, oxy c\u1ea1n ki\u1ec7t, pH gi\u1ea3m, Cl\u2212 t\u1eadp trung \u2192 m\u00e0ng th\u1ee5 \u0111\u1ed9ng suy s\u1ee5p.<br \/>\n&#8211; Thi\u1ebft k\u1ebf ch\u1ed1ng khe l\u00e0 bi\u1ec7n ph\u00e1p r\u1ebb v\u00e0 hi\u1ec7u qu\u1ea3 nh\u1ea5t.<\/p>\n<h3>\u0102n m\u00f2n tinh gi\u1edbi (intergranular) do \u201csensitization\u201d<\/h3>\n<p>&#8211; Khi h\u00e0n\/gi\u1eef 500\u2013800\u00b0C, cacbit Cr h\u00ecnh th\u00e0nh t\u1ea1i bi\u00ean h\u1ea1t, r\u00fat Cr kh\u1ecfi v\u00f9ng k\u1ec1 c\u1eadn \u2192 v\u00f9ng n\u00e0y m\u1ea5t kh\u1ea3 n\u0103ng th\u1ee5 \u0111\u1ed9ng.<br \/>\n&#8211; Kh\u1eafc ph\u1ee5c: d\u00f9ng m\u00e1c L (304L\/316L) ho\u1eb7c m\u00e1c \u1ed5n \u0111\u1ecbnh h\u00f3a 321(Ti), 347(Nb); x\u1eed l\u00fd nhi\u1ec7t \u0111\u00fang; l\u00e0m s\u1ea1ch sau h\u00e0n.<\/p>\n<h3>N\u1ee9t \u0103n m\u00f2n \u1ee9ng su\u1ea5t (SCC) trong clorua<\/h3>\n<p>&#8211; Austenitic Ni cao (304\/316) d\u1ec5 SCC \u1edf T>60\u00b0C, clorua v\u00e0 k\u00e9o. Ferritic\/duplex kh\u00e1ng SCC t\u1ed1t h\u01a1n.<\/p>\n<h2 id=\"toc-4-pren-chi-so-du-bao-chong-an-mon-lo\">PREN: ch\u1ec9 s\u1ed1 d\u1ef1 b\u00e1o ch\u1ed1ng \u0103n m\u00f2n l\u1ed7<\/h2>\n<p>&#8211; C\u00f4ng th\u1ee9c ph\u1ed5 bi\u1ebfn: PREN = %Cr + 3,3\u00d7%Mo + 16\u00d7%N.<br \/>\n&#8211; Gi\u00e1 tr\u1ecb tham kh\u1ea3o:<br \/>\n  &#8211; 201: ~16\u201318 (Cr ~16\u201317, Mo\u22480, N th\u1ea5p) \u2192 kh\u00e1ng pitting th\u1ea5p.<br \/>\n  &#8211; 304\/304L: ~18\u201319 \u2192 d\u00f9ng t\u1ed1t n\u1ed9i th\u1ea5t, kh\u00f4 r\u00e1o; kh\u00f4ng khuy\u1ebfn ngh\u1ecb g\u1ea7n bi\u1ec3n.<br \/>\n  &#8211; 316\/316L: ~24\u201326 \u2192 ph\u00f9 h\u1ee3p khu v\u1ef1c ven bi\u1ec3n, th\u1ef1c ph\u1ea9m, h\u00f3a ch\u1ea5t nh\u1eb9.<br \/>\n  &#8211; 430 (ferritic): ~16\u201317 \u2192 ch\u1ed1ng g\u1ec9 k\u00e9m h\u01a1n 304, h\u1ee3p m\u00f4i tr\u01b0\u1eddng kh\u00f4.<br \/>\n  &#8211; 2205 duplex: ~34\u201338 \u2192 kh\u00e1ng pitting\/khe cao, khuy\u1ebfn ngh\u1ecb n\u01b0\u1edbc bi\u1ec3n, x\u1eed l\u00fd n\u01b0\u1edbc m\u1eb7n.<br \/>\n  &#8211; 904L\/6Mo: >35\u201345 \u2192 \u1ee9ng d\u1ee5ng h\u00f3a ch\u1ea5t\/clorua r\u1ea5t cao.<br \/>\n&#8211; L\u01b0u \u00fd: PREN kh\u00f4ng thay th\u1ebf th\u1eed nghi\u1ec7m th\u1ef1c t\u1ebf; b\u1ec1 m\u1eb7t, thi\u1ebft k\u1ebf, v\u1ec7 sinh \u1ea3nh h\u01b0\u1edfng m\u1ea1nh.<\/p>\n<h2 id=\"toc-5-anh-huong-moi-truong-dien-hinh-tai-viet-nam\">\u1ea2nh h\u01b0\u1edfng m\u00f4i tr\u01b0\u1eddng \u0111i\u1ec3n h\u00ecnh t\u1ea1i Vi\u1ec7t Nam<\/h2>\n<p>&#8211; Ven bi\u1ec3n (\u0110\u1ed3 S\u01a1n, S\u1ea7m S\u01a1n, Nha Trang, V\u0169ng T\u00e0u): s\u01b0\u01a1ng mu\u1ed1i, gi\u00f3 bi\u1ec3n \u2192 316L t\u1ed1i thi\u1ec3u cho ngo\u1ea1i th\u1ea5t; duplex 2205 cho k\u1ebft c\u1ea5u, lan can s\u00e1t m\u00e9p n\u01b0\u1edbc.<br \/>\n&#8211; \u0110\u00f4 th\u1ecb \u1ea9m, m\u01b0a axit nh\u1eb9: 304 d\u00f9ng \u0111\u01b0\u1ee3c n\u1ebfu v\u1ec7 sinh \u0111\u1ecbnh k\u1ef3; tr\u00e1nh \u1ed1 n\u00e2u (tea staining).<br \/>\n&#8211; Th\u1ef1c ph\u1ea9m, y t\u1ebf: 304\/316 t\u00f9y h\u00f3a ch\u1ea5t CIP; tr\u00e1nh d\u00f9ng Javen (NaClO) l\u00e2u tr\u00ean 304 n\u00f3ng.<br \/>\n&#8211; X\u1eed l\u00fd n\u01b0\u1edbc, RO, b\u1ed3n ch\u1ee9a: 316L\/duplex; ki\u1ec3m so\u00e1t khe, ch\u1ecdn gio\u0103ng ph\u00f9 h\u1ee3p.<\/p>\n<h2 id=\"toc-6-xu-ly-be-mat-de-duy-tri-tinh-thu-dong\">X\u1eed l\u00fd b\u1ec1 m\u1eb7t \u0111\u1ec3 duy tr\u00ec t\u00ednh th\u1ee5 \u0111\u1ed9ng<\/h2>\n<h3>Sau gia c\u00f4ng\/h\u00e0n<\/h3>\n<p>&#8211; Lo\u1ea1i b\u1ecf v\u00f9ng bi\u1ebfn m\u00e0u (heat tint) v\u00e0 x\u1ec9 h\u00e0n: pickling b\u1eb1ng h\u1ed7n h\u1ee3p axit theo ti\u00eau chu\u1ea9n (v\u00ed d\u1ee5 ASTM A380\/A967), r\u1eeda \u00e1p l\u1ef1c cao, trung h\u00f2a, s\u1ea5y kh\u00f4.<br \/>\n&#8211; Passivation: d\u00f9ng axit nitric ho\u1eb7c axit citric theo ASTM A967 \u0111\u1ec3 l\u00e0m gi\u00e0u Cr b\u1ec1 m\u1eb7t, gi\u00fap m\u00e0ng th\u1ee5 \u0111\u1ed9ng \u1ed5n \u0111\u1ecbnh.<br \/>\n&#8211; Kh\u00f4ng d\u00f9ng HCl cho inox; h\u1ea1n ch\u1ebf ch\u00e0 th\u00e9p c\u00e1c-bon (g\u00e2y nhi\u1ec5m s\u1eaft).<\/p>\n<h3>V\u1ec7 sinh \u0111\u1ecbnh k\u1ef3<\/h3>\n<p>&#8211; T\u1ea7n su\u1ea5t: ven bi\u1ec3n 1\u20133 th\u00e1ng\/l\u1ea7n; \u0111\u00f4 th\u1ecb 3\u20136 th\u00e1ng\/l\u1ea7n.<br \/>\n&#8211; D\u1ee5ng c\u1ee5\/ch\u1ea5t t\u1ea9y: kh\u0103n m\u1ec1m, n\u01b0\u1edbc s\u1ea1ch, ch\u1ea5t t\u1ea9y trung t\u00ednh pH\u22487; r\u1eeda tr\u00e1ng k\u1ef9.<br \/>\n&#8211; Tr\u00e1nh: ch\u1ea5t t\u1ea9y ch\u1ee9a clorua, Javen n\u00f3ng, b\u1ed9t m\u00e0i th\u00f4. N\u1ebfu c\u00f3 \u1ed1 n\u00e2u nh\u1eb9, d\u00f9ng gel t\u1ea9y chuy\u00ean d\u1ee5ng cho inox, sau \u0111\u00f3 r\u1eeda s\u1ea1ch.<\/p>\n<h3>\u0110\u1ed9 nh\u00e1m v\u00e0 ho\u00e0n thi\u1ec7n b\u1ec1 m\u1eb7t<\/h3>\n<p>&#8211; B\u1ec1 m\u1eb7t c\u00e0ng m\u1ecbn (BA, No.4 m\u1ecbn, electropolish) c\u00e0ng \u00edt gi\u1eef mu\u1ed1i\/b\u1ee5i \u2192 kh\u00e1ng \u1ed1 v\u00e0 pitting t\u1ed1t h\u01a1n. M\u1ee5c ti\u00eau Ra th\u1ea5p (v\u00ed d\u1ee5 <0,5\u20130,8 \u03bcm cho ngo\u1ea1i th\u1ea5t ven bi\u1ec3n).\n\n\n\n<h2 id=\"toc-7-thiet-ke-chong-an-mon-quy-tac-thuc-tien\">Thi\u1ebft k\u1ebf ch\u1ed1ng \u0103n m\u00f2n: quy t\u1eafc th\u1ef1c ti\u1ec5n<\/h2>\n<p>&#8211; Tr\u00e1nh khe h\u1edf, \u01b0u ti\u00ean h\u00e0n li\u00ean t\u1ee5c thay v\u00ec gh\u00e9p ch\u1ed3ng\/b\u1eaft v\u00edt h\u1edf.<br \/>\n&#8211; T\u1ea1o tho\u00e1t n\u01b0\u1edbc v\u00e0 th\u00f4ng gi\u00f3; kh\u00f4ng \u0111\u1ec3 \u0111\u1ecdng n\u01b0\u1edbc mu\u1ed1i.<br \/>\n&#8211; C\u00e1ch ly \u0111i\u1ec7n gi\u1eefa inox v\u00e0 th\u00e9p c\u00e1c-bon\/nh\u00f4m trong m\u00f4i tr\u01b0\u1eddng \u1ea9m (mi\u1ebfng \u0111\u1ec7m nh\u1ef1a, s\u01a1n c\u00e1ch \u0111i\u1ec7n) \u0111\u1ec3 gi\u1ea3m \u0103n m\u00f2n \u0111i\u1ec7n h\u00f3a.<br \/>\n&#8211; Ch\u1ecdn gio\u0103ng\/ph\u1edbt \u00edt gi\u1eef mu\u1ed1i; tr\u00e1nh mastic ch\u1ee9a clorua.<br \/>\n&#8211; Kh\u00f4ng \u0111\u1ec3 b\u1ec1 m\u1eb7t ti\u1ebfp x\u00fac tr\u1ef1c ti\u1ebfp b\u00ea t\u00f4ng \u01b0\u1edbt l\u00e2u ng\u00e0y c\u00f3 clorua; d\u00f9ng l\u1edbp ng\u0103n.<\/p>\n<h2 id=\"toc-8-304-316-201-430-duplex-chon-mac-nao\">304, 316, 201, 430, duplex: ch\u1ecdn m\u00e1c n\u00e0o?<\/h2>\n<p>&#8211; 201: kinh t\u1ebf, d\u00f9ng n\u1ed9i th\u1ea5t kh\u00f4, trang tr\u00ed trong nh\u00e0. Kh\u00f4ng khuy\u1ebfn ngh\u1ecb ven bi\u1ec3n\/ngo\u00e0i tr\u1eddi.<br \/>\n&#8211; 430: t\u1eeb t\u00ednh, r\u1ebb; h\u1ee3p m\u00f4i tr\u01b0\u1eddng kh\u00f4, thi\u1ebft b\u1ecb gia d\u1ee5ng; kh\u00e1ng \u0103n m\u00f2n th\u1ea5p.<br \/>\n&#8211; 304\/304L: ph\u1ed5 bi\u1ebfn, d\u1ec5 gia c\u00f4ng; d\u00f9ng trong nh\u00e0 x\u01b0\u1edfng kh\u00f4, th\u1ef1c ph\u1ea9m kh\u00f4ng clorua m\u1ea1nh; c\u1ea7n v\u1ec7 sinh n\u1ebfu ngo\u00e0i tr\u1eddi.<br \/>\n&#8211; 316\/316L: c\u00f3 Mo; l\u1ef1a ch\u1ecdn \u201can to\u00e0n\u201d cho ven bi\u1ec3n, n\u01b0\u1edbc c\u00f4ng nghi\u1ec7p c\u00f3 Cl\u2212, y t\u1ebf\/h\u00f3a ch\u1ea5t nh\u1eb9.<br \/>\n&#8211; Duplex 2205: khi c\u1ea7n c\u01a1 t\u00ednh cao v\u00e0 kh\u00e1ng pitting\/khe v\u01b0\u1ee3t tr\u1ed9i (n\u01b0\u1edbc bi\u1ec3n, k\u1ebft c\u1ea5u b\u1edd k\u00e8, x\u1eed l\u00fd n\u01b0\u1edbc m\u1eb7n).<\/p>\n<h2 id=\"toc-9-nhan-biet-va-xu-ly-o-tra-so-voi-gi-that\">Nh\u1eadn bi\u1ebft v\u00e0 x\u1eed l\u00fd \u201c\u1ed1 tr\u00e0\u201d so v\u1edbi g\u1ec9 th\u1eadt<\/h2>\n<p>&#8211; \u1ed0 tr\u00e0: l\u1edbp nhu\u1ed9m n\u00e2u do h\u1ea1t s\u1eaft b\u1ee5i b\u00e1m + mu\u1ed1i; b\u1ec1 m\u1eb7t d\u01b0\u1edbi v\u1eabn l\u00e0 inox. Th\u01b0\u1eddng t\u1ea9y s\u1ea1ch \u0111\u01b0\u1ee3c b\u1eb1ng ch\u1ea5t t\u1ea9y chuy\u00ean d\u1ee5ng\/axit nh\u1eb9 theo h\u01b0\u1edbng d\u1eabn.<br \/>\n&#8211; G\u1ec9 th\u1eadt (\u0103n m\u00f2n): xu\u1ea5t hi\u1ec7n l\u1ed7, r\u1ed7, bong m\u1ea3ng; c\u1ea7n \u0111\u00e1nh gi\u00e1 nguy\u00ean nh\u00e2n (clorua, khe, nhi\u1ec5m Fe), l\u00e0m s\u1ea1ch, pickling\/passivation l\u1ea1i; c\u00f3 th\u1ec3 ph\u1ea3i thay chi ti\u1ebft n\u1ebfu \u0111\u00e3 th\u1ee7ng.<\/p>\n<h2 id=\"toc-10-kiem-tra-va-tieu-chuan-lien-quan\">Ki\u1ec3m tra v\u00e0 ti\u00eau chu\u1ea9n li\u00ean quan<\/h2>\n<p>&#8211; L\u00e0m s\u1ea1ch\/passivation: ASTM A380\/A380M; ASTM A967\/A967M (axit nitric\/citric).<br \/>\n&#8211; Kh\u1ea3 n\u0103ng pitting\/khe: ASTM G48 (th\u1eed feri clorua); ASTM G150 (CPT \u0111i\u1ec7n h\u00f3a).<br \/>\n&#8211; S\u01b0\u01a1ng mu\u1ed1i: ISO 9227 (\u0111\u1ec3 so s\u00e1nh t\u01b0\u01a1ng \u0111\u1ed1i, kh\u00f4ng thay th\u1ebf th\u1eed nghi\u1ec7m hi\u1ec7n tr\u01b0\u1eddng).<br \/>\n&#8211; Thu\u1eadt ng\u1eef \u0103n m\u00f2n: ISO 8044.<br \/>\n&#8211; M\u00f4i tr\u01b0\u1eddng H2S\/chua: NACE MR0175\/ISO 15156 (l\u1ef1a ch\u1ecdn v\u1eadt li\u1ec7u cho d\u1ea7u kh\u00ed).<\/p>\n<h2 id=\"toc-11-vi-du-ung-dung-nhanh\">V\u00ed d\u1ee5 \u1ee9ng d\u1ee5ng nhanh<\/h2>\n<p>&#8211; Lan can kh\u00e1ch s\u1ea1n s\u00e1t bi\u1ec3n Nha Trang: ch\u1ecdn 316L ho\u1eb7c 2205; ho\u00e0n thi\u1ec7n No.4 m\u1ecbn ho\u1eb7c electropolish; tr\u00e1nh khe, v\u1ec7 sinh 1\u20132 th\u00e1ng\/l\u1ea7n.<br \/>\n&#8211; B\u1ed3n pha n\u01b0\u1edbc mu\u1ed1i 2\u20133% \u1edf 30\u00b0C: 316L t\u1ed1i thi\u1ec3u; n\u1ebfu nhi\u1ec7t \u0111\u1ed9 >40\u00b0C, xem x\u00e9t duplex 2205.<br \/>\n&#8211; D\u00e2y chuy\u1ec1n CIP v\u1edbi HNO3 lo\u00e3ng: 304\/316 ho\u1ea1t \u0111\u1ed9ng t\u1ed1t; tr\u00e1nh HCl; ki\u1ec3m so\u00e1t nhi\u1ec7t v\u00e0 n\u1ed3ng \u0111\u1ed9.<\/p>\n<h2 id=\"toc-12-tai-lieu-tham-khao\">T\u00e0i li\u1ec7u tham kh\u1ea3o<\/h2>\n<p>&#8211; ASTM A967\/A967M \u2013 Standard Specification for Chemical Passivation Treatments for Stainless Steel Parts.<br \/>\n&#8211; ASTM A380\/A380M \u2013 Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts.<br \/>\n&#8211; ASTM G48; ASTM G150 \u2013 Pitting\/CPT testing methods for stainless steels.<br \/>\n&#8211; ISO 8044 \u2013 Corrosion of metals and alloys \u2014 Basic terms and definitions.<br \/>\n&#8211; ISO 9227 \u2013 Corrosion tests in artificial atmospheres \u2014 Salt spray tests.<br \/>\n&#8211; NACE MR0175\/ISO 15156 \u2013 Materials for use in H2S-containing environments in oil and gas production.<br \/>\n&#8211; Nickel Institute: Guidelines for corrosion resistant stainless steels; Technical Series publications.<br \/>\n&#8211; Outokumpu Stainless Steel Handbook.<br \/>\n&#8211; ASM Handbook, Vol. 13A: Corrosion: Fundamentals, Testing, and Protection.<br \/>\n&#8211; International Molybdenum Association (IMOA): Molybdenum\u2019s role in stainless steel corrosion resistance.<\/p>\n<h2 id=\"toc-13-ket-luan\">K\u1ebft lu\u1eadn<\/h2>\n<p>&#8211; Kh\u1ea3 n\u0103ng ch\u1ed1ng g\u1ec9 c\u1ee7a inox \u0111\u1ebfn t\u1eeb l\u1edbp m\u00e0ng Cr2O3 th\u1ee5 \u0111\u1ed9ng si\u00eau m\u1ecfng, t\u1ef1 ph\u1ee5c h\u1ed3i khi c\u00f3 oxy.<br \/>\n&#8211; Mo v\u00e0 N n\u00e2ng \u0111\u00e1ng k\u1ec3 kh\u00e1ng \u0103n m\u00f2n c\u1ee5c b\u1ed9; PREN gi\u00fap so s\u00e1nh nhanh gi\u1eefa c\u00e1c m\u00e1c.<br \/>\n&#8211; Clorua, khe h\u1edf, nhi\u1ec7t \u0111\u1ed9 cao, nhi\u1ec5m s\u1eaft v\u00e0 x\u1eed l\u00fd h\u00e0n sai l\u00e0 c\u00e1c nguy\u00ean nh\u00e2n ch\u00ednh ph\u00e1 v\u1ee1 m\u00e0ng th\u1ee5 \u0111\u1ed9ng.<br \/>\n&#8211; L\u1ef1a ch\u1ecdn m\u00e1c \u0111\u00fang theo m\u00f4i tr\u01b0\u1eddng, thi\u1ebft k\u1ebf gi\u1ea3m khe, ho\u00e0n thi\u1ec7n b\u1ec1 m\u1eb7t m\u1ecbn v\u00e0 v\u1ec7 sinh \u0111\u1ecbnh k\u1ef3 l\u00e0 \u201cb\u1ed9 t\u1ee9\u201d \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 b\u1ec1n l\u00e2u d\u00e0i.<br \/>\nC\u1ea7n t\u01b0 v\u1ea5n ch\u1ecdn m\u00e1c inox, quy tr\u00ecnh x\u1eed l\u00fd b\u1ec1 m\u1eb7t hay b\u00e1o gi\u00e1 t\u1ed1t nh\u1ea5t cho d\u1ef1 \u00e1n c\u1ee7a b\u1ea1n? Li\u00ean h\u1ec7 Inox C\u01b0\u1eddng Th\u1ecbnh. Hotline: 0343.417.281. Email: inoxcongnghiep.cuongthinh@gmail.com<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Inox ch\u1ed1ng g\u1ec9 nh\u1edd l\u1edbp m\u00e0ng crom th\u1ee5 \u0111\u1ed9ng si\u00eau m\u1ecfng, t\u1ef1 ph\u1ee5c h\u1ed3i. T\u00ecm hi\u1ec3u c\u01a1 ch\u1ebf, y\u1ebfu t\u1ed1 ph\u00e1 h\u1ee7y, so s\u00e1nh 304\/316, PREN, \u0103n m\u00f2n l\u1ed7 v\u00e0 c\u00e1ch b\u1ea3o tr\u00ec.<\/p>\n","protected":false},"author":7,"featured_media":1063,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[23],"tags":[],"class_list":["post-1551","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tin-tuc"],"acf":[],"_links":{"self":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/1551","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/comments?post=1551"}],"version-history":[{"count":0,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/posts\/1551\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media\/1063"}],"wp:attachment":[{"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/media?parent=1551"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/categories?post=1551"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inoxcuongthinh.com\/inct\/wp\/v2\/tags?post=1551"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}