{"id":2108,"date":"2016-03-01T14:32:28","date_gmt":"2016-03-01T14:32:28","guid":{"rendered":"https:\/\/wldstainless.com\/?p=2108"},"modified":"2021-03-01T14:41:27","modified_gmt":"2021-03-01T14:41:27","slug":"why-does-stainless-steel-corrode","status":"publish","type":"post","link":"https:\/\/wldstainless.com\/vi\/why-does-stainless-steel-corrode\/","title":{"rendered":"T\u1ea1i sao th\u00e9p kh\u00f4ng g\u1ec9 b\u1ecb \u0103n m\u00f2n?"},"content":{"rendered":"<p>Nh\u01b0 ch\u00fang ta bi\u1ebft, <a href=\"https:\/\/wldstainless.com\/materials\/austenitic-stainless-steel\/304-304l-stainless-steel\/\">th\u00e9p kh\u00f4ng g\u1ec9<\/a> c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng l\u1ea1i qu\u00e1 tr\u00ecnh oxy h\u00f3a trong kh\u00ed quy\u1ec3n, ngh\u0129a l\u00e0 kh\u00f4ng b\u1ecb r\u1ec9 s\u00e9t m\u00e0 c\u00f2n b\u1ecb \u0103n m\u00f2n trong m\u00f4i tr\u01b0\u1eddng nh\u01b0 axit, ki\u1ec1m v\u00e0 mu\u1ed1i, t\u1ee9c l\u00e0 ch\u1ed1ng \u0103n m\u00f2n. Tuy nhi\u00ean, kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 l\u00e0 c\u00f3 \u0111i\u1ec1u ki\u1ec7n, ngh\u0129a l\u00e0 th\u00e9p kh\u00f4ng g\u1ec9 \u1edf m\u1ed9t m\u00f4i tr\u01b0\u1eddng nh\u1ea5t \u0111\u1ecbnh c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n nh\u01b0ng \u1edf m\u1ed9t m\u00f4i tr\u01b0\u1eddng kh\u00e1c c\u00f3 th\u1ec3 b\u1ecb ph\u00e1 h\u1ee7y. T\u01b0\u01a1ng \u1ee9ng, kh\u00f4ng c\u00f3 lo\u1ea1i th\u00e9p kh\u00f4ng g\u1ec9 n\u00e0o c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n trong m\u1ecdi m\u00f4i tr\u01b0\u1eddng.<\/p>\n<p>Th\u00e9p kh\u00f4ng g\u1ec9 c\u00f3 th\u1ec3 cung c\u1ea5p kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n tuy\u1ec7t v\u1eddi trong c\u00e1c ng\u00e0nh c\u00f4ng nghi\u1ec7p kh\u00e1c nhau, n\u00f3i \u0111\u00fang ra, ch\u00fang cho th\u1ea5y kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n tuy\u1ec7t v\u1eddi trong h\u1ea7u h\u1ebft c\u00e1c ph\u01b0\u01a1ng ti\u1ec7n, nh\u01b0ng n\u00f3 \u0111\u1eb7c bi\u1ec7t trong m\u1ed9t s\u1ed1 ph\u01b0\u01a1ng ti\u1ec7n do \u0111\u1ed9 \u1ed5n \u0111\u1ecbnh h\u00f3a h\u1ecdc v\u00e0 \u0103n m\u00f2n th\u1ea5p. Do \u0111\u00f3, th\u00e9p kh\u00f4ng g\u1ec9 kh\u00f4ng th\u1ec3 ch\u1ed1ng \u0103n m\u00f2n cho t\u1ea5t c\u1ea3 c\u00e1c ph\u01b0\u01a1ng ti\u1ec7n ngo\u1ea1i tr\u1eeb h\u01b0 h\u1ecfng c\u01a1 h\u1ecdc. S\u1ef1 \u0103n m\u00f2n c\u1ee7a <a href=\"https:\/\/wldstainless.com\/materials\/austenitic-stainless-steel\/304-304l-stainless-steel\/\">th\u00e9p kh\u00f4ng g\u1ec9<\/a> Bi\u1ec3u hi\u1ec7n ch\u1ee7 y\u1ebfu l\u00e0 m\u1ed9t d\u1ea1ng \u0103n m\u00f2n nghi\u00eam tr\u1ecdng c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 l\u00e0 \u0103n m\u00f2n c\u1ee5c b\u1ed9 (t\u1ee9c l\u00e0 n\u1ee9t do \u0103n m\u00f2n \u1ee9ng su\u1ea5t, r\u1ed7, \u0103n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t, \u0103n m\u00f2n m\u1ecfi v\u00e0 \u0103n m\u00f2n k\u1ebd h\u1edf). S\u1ef1 \u0103n m\u00f2n c\u1ee5c b\u1ed9 n\u00e0y g\u00e2y ra g\u1ea7n m\u1ed9t n\u1eeda s\u1ed1 l\u1ed7i. \u0110\u1ec3 hi\u1ec3u t\u1ea1i sao th\u00e9p kh\u00f4ng g\u1ec9 b\u1ecb \u0103n m\u00f2n, tr\u01b0\u1edbc ti\u00ean ch\u00fang ta ph\u1ea3i hi\u1ec3u lo\u1ea1i \u0103n m\u00f2n c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9.<\/p>\n<p>&nbsp;<\/p>\n<p><strong><b>N\u1ee9t \u0103n m\u00f2n \u1ee9ng su\u1ea5t (SCC)<\/b><\/strong><\/p>\n<p>N\u1ee9t \u0103n m\u00f2n \u1ee9ng su\u1ea5t (SCC) l\u00e0 s\u1ef1 h\u01b0 h\u1ecfng c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 ch\u1ecbu \u1ee9ng su\u1ea5t trong m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n do s\u1ef1 gi\u00e3n n\u1edf c\u1ee7a h\u1ea1t m\u1ea1nh. SCC c\u00f3 h\u00ecnh th\u00e1i g\u00e3y gi\u00f2n v\u00e0 c\u00f3 th\u1ec3 x\u1ea3y ra \u1edf c\u00e1c v\u1eadt li\u1ec7u c\u00f3 \u0111\u1ed9 b\u1ec1n cao khi c\u00f3 \u1ee9ng su\u1ea5t k\u00e9o (d\u00f9 l\u00e0 \u1ee9ng su\u1ea5t d\u01b0 hay \u1ee9ng su\u1ea5t t\u00e1c d\u1ee5ng ho\u1eb7c c\u1ea3 hai) v\u00e0 m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n. Theo thu\u1eadt ng\u1eef vi m\u00f4, v\u1ebft n\u1ee9t xuy\u00ean qua h\u1ea1t \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 v\u1ebft n\u1ee9t xuy\u00ean h\u1ea1t v\u00e0 c\u00e1c v\u1ebft n\u1ee9t d\u1ecdc theo bi\u1ec3u \u0111\u1ed3 gi\u00e3n n\u1edf ranh gi\u1edbi h\u1ea1t \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 v\u1ebft n\u1ee9t gi\u1eefa c\u00e1c h\u1ea1t, khi SCC m\u1edf r\u1ed9ng \u0111\u1ebfn m\u1ed9t \u0111\u1ed9 s\u00e2u (\u1ee9ng su\u1ea5t t\u1ea3i l\u00ean ph\u1ea7n v\u1eadt li\u1ec7u \u0111\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c \u1ee9ng su\u1ea5t g\u00e3y c\u1ee7a n\u00f3) trong kh\u00f4ng kh\u00ed, <a href=\"https:\/\/wldstainless.com\/materials\/austenitic-stainless-steel\/304-304l-stainless-steel\/\">th\u00e9p kh\u00f4ng g\u1ec9<\/a> nh\u01b0 v\u1ebft n\u1ee9t th\u00f4ng th\u01b0\u1eddng (trong v\u1eadt li\u1ec7u d\u1ebbo, th\u01b0\u1eddng l\u00e0 do s\u1ef1 k\u1ebft t\u1ee5 c\u00e1c khuy\u1ebft t\u1eadt vi m\u00f4) v\u00e0 ng\u1eaft k\u1ebft n\u1ed1i.<\/p>\n<p>Do \u0111\u00f3, ph\u1ea7n c\u1ee7a b\u1ed9 ph\u1eadn b\u1ecb h\u1ecfng do n\u1ee9t do \u0103n m\u00f2n \u1ee9ng su\u1ea5t s\u1ebd ch\u1ee9a c\u00e1c khu v\u1ef1c \u0111\u01b0\u1ee3c \u0111\u1eb7c tr\u01b0ng b\u1edfi v\u1ebft n\u1ee9t \u0103n m\u00f2n do \u1ee9ng su\u1ea5t v\u00e0 c\u00e1c khu v\u1ef1c \u201cl\u00fam \u0111\u1ed3ng ti\u1ec1n\u201d li\u00ean quan \u0111\u1ebfn qu\u00e1 tr\u00ecnh tr\u00f9ng h\u1ee3p b\u1ecb khi\u1ebfm khuy\u1ebft nh\u1eb9.<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u0103n m\u00f2n r\u1ed7<\/strong><\/p>\n<p>\u0102n m\u00f2n r\u1ed7 \u0111\u1ec1 c\u1eadp \u0111\u1ebfn s\u1ef1 \u0103n m\u00f2n c\u1ee5c b\u1ed9 kh\u00f4ng b\u1ecb \u0103n m\u00f2n ho\u1eb7c r\u1ea3i r\u00e1c nh\u1ea5t tr\u00ean b\u1ec1 m\u1eb7t v\u1eadt li\u1ec7u kim lo\u1ea1i. K\u00edch th\u01b0\u1edbc c\u1ee7a \u0111i\u1ec3m r\u1ed7 th\u00f4ng th\u01b0\u1eddng nh\u1ecf h\u01a1n 1,00mm v\u00e0 \u0111\u1ed9 s\u00e2u th\u01b0\u1eddng l\u1edbn h\u01a1n kh\u1ea9u \u0111\u1ed9 b\u1ec1 m\u1eb7t, c\u00f3 th\u1ec3 l\u00e0 h\u1ed1 r\u1ed7 n\u00f4ng ho\u1eb7c th\u1ee7ng.<\/p>\n<p>&nbsp;<\/p>\n<p><strong>S\u1ef1 \u0103n m\u00f2n li\u00ean v\u00f9ng<\/strong><\/p>\n<p>\u0102n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t: S\u1ef1 ph\u00e2n b\u1ed1 kh\u00f4ng \u0111\u1ec1u c\u1ee7a c\u00e1c h\u1ea1t \u1edf ranh gi\u1edbi gi\u1eefa c\u00e1c h\u1ea1t kh\u00e1c nhau v\u00e0 do \u0111\u00f3 l\u00e0 v\u00f9ng thu\u1eadn l\u1ee3i cho s\u1ef1 ph\u00e2n t\u00e1ch c\u00e1c nguy\u00ean t\u1ed1 h\u00f2a tan ho\u1eb7c k\u1ebft t\u1ee7a c\u00e1c h\u1ee3p ch\u1ea5t kim lo\u1ea1i nh\u01b0 cacbua v\u00e0 pha \u03b4 trong th\u00e9p. Do \u0111\u00f3, trong m\u1ed9t s\u1ed1 m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n, th\u00f4ng th\u01b0\u1eddng ranh gi\u1edbi h\u1ea1t c\u00f3 th\u1ec3 b\u1ecb \u0103n m\u00f2n tr\u01b0\u1edbc ti\u00ean v\u00e0 h\u1ea7u h\u1ebft c\u00e1c kim lo\u1ea1i v\u00e0 h\u1ee3p kim c\u00f3 th\u1ec3 bi\u1ec3u hi\u1ec7n s\u1ef1 \u0103n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t trong m\u1ed9t s\u1ed1 m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n nh\u1ea5t \u0111\u1ecbnh.<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u0110\u01b0\u1eddng n\u1ee9t \u0103n m\u00f2n<\/strong><\/p>\n<p>\u0102n m\u00f2n k\u1ebd h\u1edf \u0111\u1ec1 c\u1eadp \u0111\u1ebfn s\u1ef1 xu\u1ea5t hi\u1ec7n c\u1ee7a s\u1ef1 \u0103n m\u00f2n l\u1ed1m \u0111\u1ed1m trong c\u00e1c v\u1ebft n\u1ee9t c\u1ee7a c\u00e1c b\u1ed9 ph\u1eadn b\u1eb1ng th\u00e9p kh\u00f4ng g\u1ec9, l\u00e0 m\u1ed9t lo\u1ea1i \u0103n m\u00f2n c\u1ee5c b\u1ed9. N\u00f3 c\u00f3 th\u1ec3 x\u1ea3y ra trong c\u00e1c v\u1ebft n\u1ee9t do dung d\u1ecbch \u0111\u1ecdng l\u1ea1i ho\u1eb7c tr\u00ean b\u1ec1 m\u1eb7t che ch\u1eafn. Nh\u1eefng kho\u1ea3ng tr\u1ed1ng nh\u01b0 v\u1eady c\u00f3 th\u1ec3 h\u00ecnh th\u00e0nh t\u1ea1i c\u00e1c m\u1ed1i n\u1ed1i kim lo\u1ea1i v\u1edbi kim lo\u1ea1i ho\u1eb7c kim lo\u1ea1i v\u1edbi phi kim lo\u1ea1i, v\u00ed d\u1ee5 nh\u01b0 \u1edf \u0111inh t\u00e1n, bu l\u00f4ng, mi\u1ebfng \u0111\u1ec7m, \u0111\u1ebf van v\u00e0 c\u1eb7n b\u1ec1 m\u1eb7t l\u1ecfng l\u1ebbo.<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u0102n m\u00f2n chung<\/strong><\/p>\n<p>\u0102n m\u00f2n \u0111\u1ed3ng \u0111\u1ec1u tr\u00ean b\u1ec1 m\u1eb7t th\u00e9p kh\u00f4ng g\u1ec9. Th\u00e9p kh\u00f4ng g\u1ec9 c\u00f3 th\u1ec3 bi\u1ec3u hi\u1ec7n s\u1ef1 \u0103n m\u00f2n n\u00f3i chung trong axit v\u00e0 baz\u01a1 m\u1ea1nh. Khi s\u1ef1 \u0103n m\u00f2n n\u00f3i chung x\u1ea3y ra, th\u00e9p kh\u00f4ng g\u1ec9 d\u1ea7n d\u1ea7n m\u1ecfng \u0111i v\u00e0 th\u1eadm ch\u00ed b\u1ecb h\u1ecfng, \u0111i\u1ec1u n\u00e0y kh\u00f4ng \u0111\u00e1ng lo ng\u1ea1i l\u1eafm v\u00ec s\u1ef1 \u0103n m\u00f2n nh\u01b0 v\u1eady th\u01b0\u1eddng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c d\u1ef1 \u0111o\u00e1n b\u1eb1ng th\u1eed nghi\u1ec7m ng\u00e2m \u0111\u01a1n gi\u1ea3n. C\u00f3 th\u1ec3 n\u00f3i, th\u00e9p kh\u00f4ng g\u1ec9 d\u00f9ng \u0111\u1ec3 ch\u1ec9 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n c\u1ee7a th\u00e9p trong kh\u00ed quy\u1ec3n v\u00e0 m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n y\u1ebfu, t\u1ed1c \u0111\u1ed9 \u0103n m\u00f2n d\u01b0\u1edbi 0,01mm\/n\u0103m, t\u1ee9c l\u00e0 \u201cch\u1ed1ng \u0103n m\u00f2n ho\u00e0n to\u00e0n\u201d; Th\u00e9p kh\u00f4ng g\u1ec9 c\u00f3 t\u1ed1c \u0111\u1ed9 \u0103n m\u00f2n d\u01b0\u1edbi 0,1mm\/n\u0103m \u0111\u01b0\u1ee3c coi l\u00e0 \u201cch\u1ed1ng \u0103n m\u00f2n\u201d.<\/p>\n<p>&nbsp;<\/p>","protected":false},"excerpt":{"rendered":"<p>Nh\u01b0 ch\u00fang ta \u0111\u00e3 bi\u1ebft, th\u00e9p kh\u00f4ng g\u1ec9 c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng l\u1ea1i qu\u00e1 tr\u00ecnh oxy h\u00f3a trong kh\u00ed quy\u1ec3n, t\u1ee9c l\u00e0 kh\u00f4ng b\u1ecb r\u1ec9 s\u00e9t m\u00e0 c\u00f2n b\u1ecb \u0103n m\u00f2n trong m\u00f4i tr\u01b0\u1eddng nh\u01b0 axit, ki\u1ec1m v\u00e0 mu\u1ed1i, t\u1ee9c l\u00e0 c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n. Tuy nhi\u00ean, kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 l\u00e0 c\u00f3 \u0111i\u1ec1u ki\u1ec7n, ngh\u0129a l\u00e0 th\u00e9p kh\u00f4ng g\u1ec9 \u1edf m\u1ed9t m\u00f4i tr\u01b0\u1eddng nh\u1ea5t \u0111\u1ecbnh c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n, nh\u01b0ng \u1edf m\u1ed9t m\u00f4i tr\u01b0\u1eddng kh\u00e1c [\u2026]<\/p>","protected":false},"author":1,"featured_media":2110,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":["post-2108","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/posts\/2108","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/comments?post=2108"}],"version-history":[{"count":4,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/posts\/2108\/revisions"}],"predecessor-version":[{"id":2113,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/posts\/2108\/revisions\/2113"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/media\/2110"}],"wp:attachment":[{"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/media?parent=2108"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/categories?post=2108"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wldstainless.com\/vi\/wp-json\/wp\/v2\/tags?post=2108"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}