{"id":20221,"date":"2020-12-22T05:36:05","date_gmt":"2020-12-22T05:36:05","guid":{"rendered":"https:\/\/www.meetyoucarbide.com\/?p=20221"},"modified":"2020-12-22T05:36:08","modified_gmt":"2020-12-22T05:36:08","slug":"why-do-you-having-problems-frequently-when-welding-stainless-steel","status":"publish","type":"post","link":"https:\/\/www.meetyoucarbide.com\/vi\/why-do-you-having-problems-frequently-when-welding-stainless-steel\/","title":{"rendered":"T\u1ea1i sao b\u1ea1n g\u1eb7p s\u1ef1 c\u1ed1 th\u01b0\u1eddng xuy\u00ean khi h\u00e0n th\u00e9p kh\u00f4ng g\u1ec9?"},"content":{"rendered":"
\n

\u0110\u1eb7c t\u00ednh h\u00e0n c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 austenit: \u1ee9ng su\u1ea5t v\u00e0 bi\u1ebfn d\u1ea1ng \u0111\u00e0n h\u1ed3i v\u00e0 d\u1ebbo r\u1ea5t l\u1edbn trong qu\u00e1 tr\u00ecnh h\u00e0n, nh\u01b0ng c\u00f3 r\u1ea5t \u00edt v\u1ebft n\u1ee9t ngu\u1ed9i. M\u1ed1i h\u00e0n kh\u00f4ng c\u00f3 v\u00f9ng l\u00e0m ngu\u1ed9i v\u00e0 h\u1ea1t th\u00f4 n\u00ean \u0111\u1ed9 b\u1ec1n k\u00e9o c\u1ee7a m\u1ed1i h\u00e0n cao.<\/p>\n\n\n\n

C\u00e1c v\u1ea5n \u0111\u1ec1 ch\u00ednh c\u1ee7a h\u00e0n th\u00e9p kh\u00f4ng g\u1ec9 austenit l\u00e0: bi\u1ebfn d\u1ea1ng h\u00e0n l\u1edbn; do \u0111\u1eb7c \u0111i\u1ec3m ranh gi\u1edbi h\u1ea1t v\u00e0 \u0111\u1ed9 nh\u1ea1y c\u1ea3m v\u1edbi m\u1ed9t s\u1ed1 t\u1ea1p ch\u1ea5t vi l\u01b0\u1ee3ng (s, P), d\u1ec5 t\u1ea1o ra c\u00e1c v\u1ebft n\u1ee9t n\u00f3ng.<\/p>\n\n\n\n

N\u0103m v\u1ea5n \u0111\u1ec1 h\u00e0n ch\u00ednh v\u00e0 bi\u1ec7n ph\u00e1p x\u1eed l\u00fd th\u00e9p kh\u00f4ng g\u1ec9 austenit<\/p>\n\n\n\n

S\u1ef1 h\u00ecnh th\u00e0nh cacbua crom l\u00e0m gi\u1ea3m kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t c\u1ee7a m\u1ed1i h\u00e0n<\/h2>\n\n\n\n

\u0102n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t: theo l\u00fd thuy\u1ebft v\u1ec1 crom k\u00e9m, khi m\u1ed1i h\u00e0n v\u00e0 v\u00f9ng ch\u1ecbu \u1ea3nh h\u01b0\u1edfng nhi\u1ec7t \u0111\u01b0\u1ee3c nung n\u00f3ng \u0111\u1ebfn v\u00f9ng nhi\u1ec7t \u0111\u1ed9 nh\u1ea1y c\u1ea3m 450 ~ 850oC, cacbua crom k\u1ebft t\u1ee7a tr\u00ean ranh gi\u1edbi h\u1ea1t, d\u1eabn \u0111\u1ebfn ranh gi\u1edbi h\u1ea1t crom k\u00e9m, kh\u00f4ng \u0111\u1ee7 \u0111\u1ec3 ch\u1ed1ng l\u1ea1i \u0103n m\u00f2n. S\u1ed1 kh\u00f4ng<\/p>\n\n\n\n

(1) C\u00f3 th\u1ec3 \u00e1p d\u1ee5ng c\u00e1c bi\u1ec7n ph\u00e1p sau \u0111\u00e2y \u0111\u1ec3 h\u1ea1n ch\u1ebf s\u1ef1 \u0103n m\u00f2n gi\u1eefa c\u00e1c h\u1ea1t c\u1ee7a m\u1ed1i h\u00e0n v\u00e0 s\u1ef1 \u0103n m\u00f2n v\u00f9ng nhi\u1ec7t \u0111\u1ed9 nh\u1ea1y c\u1ea3m tr\u00ean v\u1eadt li\u1ec7u m\u1ee5c ti\u00eau<\/p>\n\n\n\n

M\u1ed9t. \u0110\u1ec3 tr\u00e1nh s\u1ef1 h\u00ecnh th\u00e0nh Cr23C6, c\u00e1c nguy\u00ean t\u1ed1 \u1ed5n \u0111\u1ecbnh nh\u01b0 Ti v\u00e0 Nb \u0111\u01b0\u1ee3c th\u00eam v\u00e0o kim lo\u1ea1i c\u01a1 b\u1ea3n \u0111\u1ec3 gi\u1ea3m h\u00e0m l\u01b0\u1ee3ng cacbon trong kim lo\u1ea1i c\u01a1 b\u1ea3n v\u00e0 m\u1ed1i h\u00e0n.<\/p>\n\n\n\n

b. C\u1ea5u tr\u00fac pha k\u00e9p c\u1ee7a austenite v\u00e0 m\u1ed9t l\u01b0\u1ee3ng nh\u1ecf ferit \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh trong m\u1ed1i h\u00e0n. Khi c\u00f3 m\u1ed9t l\u01b0\u1ee3ng ferit nh\u1ea5t \u0111\u1ecbnh trong m\u1ed1i h\u00e0n, k\u00edch th\u01b0\u1edbc h\u1ea1t c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c tinh ch\u1ebf, di\u1ec7n t\u00edch h\u1ea1t c\u00f3 th\u1ec3 t\u0103ng l\u00ean v\u00e0 l\u01b0\u1ee3ng k\u1ebft t\u1ee7a crom cacbua tr\u00ean m\u1ed9t \u0111\u01a1n v\u1ecb di\u1ec7n t\u00edch ranh gi\u1edbi h\u1ea1t c\u00f3 th\u1ec3 gi\u1ea3m \u0111i.<\/p>\n\n\n\n

Cr23C6 \u0111\u01b0\u1ee3c \u01b0u ti\u00ean h\u00ecnh th\u00e0nh trong ferit thay v\u00ec crom k\u00e9m \u1edf ranh gi\u1edbi h\u1ea1t austenit; ferrite gi\u1eefa austenite c\u00f3 th\u1ec3 ng\u0103n ch\u1eb7n s\u1ef1 \u0103n m\u00f2n khu\u1ebfch t\u00e1n v\u00e0o b\u00ean trong d\u1ecdc theo ranh gi\u1edbi h\u1ea1t.<\/p>\n\n\n\n

c. Ki\u1ec3m so\u00e1t th\u1eddi gian c\u01b0 tr\u00fa trong ph\u1ea1m vi nhi\u1ec7t \u0111\u1ed9 nh\u1ea1y c\u1ea3m. \u0110i\u1ec1u ch\u1ec9nh chu tr\u00ecnh nhi\u1ec7t h\u00e0n \u0111\u1ec3 r\u00fat ng\u1eafn th\u1eddi gian l\u01b0u tr\u00fa 600-1000oC c\u00e0ng nhi\u1ec1u c\u00e0ng t\u1ed1t. C\u00f3 th\u1ec3 l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p h\u00e0n c\u00f3 m\u1eadt \u0111\u1ed9 n\u0103ng l\u01b0\u1ee3ng cao (ch\u1eb3ng h\u1ea1n nh\u01b0 h\u00e0n h\u1ed3 quang argon plasma). N\u0103ng l\u01b0\u1ee3ng \u0111\u01b0\u1eddng h\u00e0n nh\u1ecf h\u01a1n. Kh\u00ed Argon \u0111\u01b0\u1ee3c c\u1ea5p v\u00e0o m\u1eb7t sau c\u1ee7a m\u1ed1i h\u00e0n ho\u1eb7c mi\u1ebfng \u0111\u1ed3ng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u0103ng t\u1ed1c \u0111\u1ed9 l\u00e0m m\u00e1t c\u1ee7a m\u1ed1i h\u00e0n. S\u1ed1 l\u1ea7n \u0111\u00e1nh h\u1ed3 quang v\u00e0 d\u1eebng h\u1ed3 quang \u0111\u01b0\u1ee3c gi\u1ea3m b\u1edbt \u0111\u1ec3 tr\u00e1nh b\u1ecb nung n\u00f3ng nhi\u1ec1u l\u1ea7n. B\u1ec1 m\u1eb7t ti\u1ebfp x\u00fac gi\u1eefa v\u1eadt h\u00e0n nhi\u1ec1u l\u1edbp v\u00e0 m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n c\u00e0ng b\u1ec1n c\u00e0ng t\u1ed1t.<\/p>\n\n\n\n

d. Sau khi h\u00e0n, n\u00ean x\u1eed l\u00fd dung d\u1ecbch r\u1eafn ho\u1eb7c \u1ee7 \u1ed5n \u0111\u1ecbnh (850-900oC) sau khi b\u1ea3o qu\u1ea3n nhi\u1ec7t v\u00e0 l\u00e0m m\u00e1t kh\u00f4ng kh\u00ed \u0111\u1ec3 k\u1ebft t\u1ee7a ho\u00e0n to\u00e0n cacbua v\u00e0 t\u0103ng t\u1ed1c \u0111\u1ed9 khu\u1ebfch t\u00e1n crom.<\/p>\n\n\n\n

(2) V\u00ec l\u00fd do n\u00e0y, c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n c\u00e1c bi\u1ec7n ph\u00e1p ph\u00f2ng ng\u1eeba sau:<\/p>\n\n\n\n

Do kh\u1ea3 n\u0103ng khu\u1ebfch t\u00e1n m\u1ea1nh c\u1ee7a carbon n\u00ean n\u00f3 s\u1ebd ph\u00e2n t\u00e1ch \u1edf ranh gi\u1edbi h\u1ea1t v\u00e0 h\u00ecnh th\u00e0nh tr\u1ea1ng th\u00e1i si\u00eau b\u00e3o h\u00f2a trong qu\u00e1 tr\u00ecnh l\u00e0m l\u1ea1nh, trong khi Ti v\u00e0 Nb s\u1ebd t\u1ed3n t\u1ea1i trong tinh th\u1ec3 do kh\u1ea3 n\u0103ng khu\u1ebfch t\u00e1n th\u1ea5p. Khi m\u1ed1i h\u00e0n \u0111\u01b0\u1ee3c nung n\u00f3ng l\u1ea1i \u1edf kho\u1ea3ng nhi\u1ec7t \u0111\u1ed9 nh\u1ea1y c\u1ea3m, cacbon si\u00eau b\u00e3o h\u00f2a s\u1ebd k\u1ebft t\u1ee7a d\u01b0\u1edbi d\u1ea1ng Cr23C6.<\/p>\n\n\n\n

M\u1ed9t. Gi\u1ea3m h\u00e0m l\u01b0\u1ee3ng cacbon. \u0110\u1ed1i v\u1edbi th\u00e9p kh\u00f4ng g\u1ec9 c\u00f3 ch\u1ee9a y\u1ebfu t\u1ed1 \u1ed5n \u0111\u1ecbnh th\u00ec h\u00e0m l\u01b0\u1ee3ng cacbon kh\u00f4ng \u0111\u01b0\u1ee3c v\u01b0\u1ee3t qu\u00e1 0,06%.<\/p>\n\n\n\n

b. Adopt reasonable welding process. In order to reduce the residence time of overheated zone at high temperature, a smaller welding line energy should be selected to avoid “medium temperature sensitization” effect in the welding process.<\/p>\n\n\n\n

Trong tr\u01b0\u1eddng h\u1ee3p h\u00e0n hai m\u1eb7t, m\u1ed1i h\u00e0n ti\u1ebfp x\u00fac v\u1edbi m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n ph\u1ea3i \u0111\u01b0\u1ee3c h\u00e0n cu\u1ed1i c\u00f9ng (\u0111\u00e2y l\u00e0 l\u00fd do t\u1ea1i sao vi\u1ec7c h\u00e0n b\u00ean trong \u1ed1ng h\u00e0n th\u00e0nh d\u00e0y \u0111\u01b0\u1eddng k\u00ednh l\u1edbn \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n sau khi h\u00e0n b\u00ean ngo\u00e0i). N\u1ebfu kh\u00f4ng th\u1ec3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c th\u00ec ph\u1ea3i \u0111i\u1ec1u ch\u1ec9nh th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt h\u00e0n v\u00e0 h\u00ecnh d\u1ea1ng m\u1ed1i h\u00e0n \u0111\u1ec3 tr\u00e1nh v\u00f9ng qu\u00e1 n\u00f3ng ti\u1ebfp x\u00fac v\u1edbi m\u00f4i tr\u01b0\u1eddng \u0103n m\u00f2n kh\u00f4ng b\u1ecb nh\u1ea1y c\u1ea3m tr\u1edf l\u1ea1i.<\/p>\n\n\n\n

c. X\u1eed l\u00fd nhi\u1ec7t sau h\u00e0n. Sau khi h\u00e0n ph\u1ea3i ti\u1ebfn h\u00e0nh x\u1eed l\u00fd b\u1eb1ng dung d\u1ecbch r\u1eafn ho\u1eb7c \u1ed5n \u0111\u1ecbnh.<\/strong><\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

n\u1ee9t \u0103n m\u00f2n \u1ee9ng su\u1ea5t<\/h2>\n\n\n\n

C\u00e1c bi\u1ec7n ph\u00e1p sau \u0111\u00e2y c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n \u0111\u1ec3 ng\u0103n ng\u1eeba s\u1ef1 xu\u1ea5t hi\u1ec7n c\u1ee7a v\u1ebft n\u1ee9t do \u0103n m\u00f2n \u1ee9ng su\u1ea5t:<\/strong><\/strong><\/p>\n\n\n\n

M\u1ed9t. L\u1ef1a ch\u1ecdn \u0111\u00fang v\u1eadt li\u1ec7u v\u00e0 \u0111i\u1ec1u ch\u1ec9nh h\u1ee3p l\u00fd th\u00e0nh ph\u1ea7n m\u1ed1i h\u00e0n. Th\u00e9p kh\u00f4ng g\u1ec9 austenit crom niken c\u00f3 \u0111\u1ed9 tinh khi\u1ebft cao, th\u00e9p kh\u00f4ng g\u1ec9 austenit crom niken silic cao, th\u00e9p kh\u00f4ng g\u1ec9 austenit ferrite v\u00e0 th\u00e9p kh\u00f4ng g\u1ec9 ferrite crom cao c\u00f3 kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n \u1ee9ng su\u1ea5t t\u1ed1t. Khi kim lo\u1ea1i h\u00e0n l\u00e0 th\u00e9p hai pha austenit ferrite, kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n \u1ee9ng su\u1ea5t l\u00e0 t\u1ed1t.<\/strong><\/strong><\/p>\n\n\n\n

b. Lo\u1ea1i b\u1ecf ho\u1eb7c gi\u1ea3m \u1ee9ng su\u1ea5t d\u01b0. \u1ee8ng su\u1ea5t d\u01b0 b\u1ec1 m\u1eb7t \u0111\u01b0\u1ee3c gi\u1ea3m \u0111i b\u1eb1ng c\u00e1ch \u0111\u00e1nh b\u00f3ng, m\u00e0i nh\u1eb5n v\u00e0 \u0111\u00f3ng b\u00faa.<\/strong><\/strong><\/p>\n\n\n\n

c. Thi\u1ebft k\u1ebf k\u1ebft c\u1ea5u h\u1ee3p l\u00fd. \u0110\u1ec3 tr\u00e1nh s\u1ef1 t\u1eadp trung \u1ee9ng su\u1ea5t l\u1edbn.<\/strong><\/strong><\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

V\u1ebft n\u1ee9t n\u00f3ng h\u00e0n (n\u1ee9t k\u1ebft tinh m\u1ed1i h\u00e0n, v\u1ebft n\u1ee9t h\u00f3a l\u1ecfng HAZ)<\/h2>\n\n\n\n

\u0110\u1ed9 nh\u1ea1y v\u1ebft n\u1ee9t n\u00f3ng ch\u1ee7 y\u1ebfu ph\u1ee5 thu\u1ed9c v\u00e0o th\u00e0nh ph\u1ea7n h\u00f3a h\u1ecdc, c\u1ea5u tr\u00fac vi m\u00f4 v\u00e0 t\u00ednh ch\u1ea5t c\u1ee7a v\u1eadt li\u1ec7u. Ni d\u1ec5 h\u00ecnh th\u00e0nh c\u00e1c h\u1ee3p ch\u1ea5t c\u00f3 \u0111i\u1ec3m n\u00f3ng ch\u1ea3y th\u1ea5p ho\u1eb7c eutectic v\u1edbi c\u00e1c t\u1ea1p ch\u1ea5t nh\u01b0 s v\u00e0 P. S\u1ef1 ph\u00e2n t\u00e1ch boron v\u00e0 silicon s\u1ebd th\u00fac \u0111\u1ea9y qu\u00e1 tr\u00ecnh n\u1ee9t n\u00f3ng.<\/strong><\/strong><\/p>\n\n\n\n

D\u1ec5 d\u00e0ng h\u00ecnh th\u00e0nh c\u1ea5u tr\u00fac tinh th\u1ec3 c\u1ed9t th\u00f4 v\u1edbi t\u00ednh \u0111\u1ecbnh h\u01b0\u1edbng m\u1ea1nh, c\u00f3 l\u1ee3i cho vi\u1ec7c ph\u00e2n t\u00e1ch c\u00e1c t\u1ea1p ch\u1ea5t v\u00e0 nguy\u00ean t\u1ed1 c\u00f3 h\u1ea1i, do \u0111\u00f3 th\u00fac \u0111\u1ea9y s\u1ef1 h\u00ecnh th\u00e0nh m\u00e0ng ch\u1ea5t l\u1ecfng gi\u1eefa c\u00e1c h\u1ea1t li\u00ean t\u1ee5c v\u00e0 c\u1ea3i thi\u1ec7n \u0111\u1ed9 nh\u1ea1y c\u1ee7a v\u1ebft n\u1ee9t n\u00f3ng. N\u1ebfu m\u1ed1i h\u00e0n \u0111\u01b0\u1ee3c l\u00e0m n\u00f3ng kh\u00f4ng \u0111\u1ec1u, d\u1ec5 h\u00ecnh th\u00e0nh \u1ee9ng su\u1ea5t k\u00e9o l\u1edbn v\u00e0 th\u00fac \u0111\u1ea9y t\u1ea1o ra c\u00e1c v\u1ebft n\u1ee9t n\u00f3ng khi h\u00e0n.<\/strong><\/strong><\/p>\n\n\n\n

Bi\u1ec7n ph\u00e1p ph\u00f2ng ng\u1eeba:<\/strong><\/strong><\/p>\n\n\n\n

M\u1ed9t. H\u00e0m l\u01b0\u1ee3ng t\u1ea1p ch\u1ea5t c\u00f3 h\u1ea1i s v\u00e0 P c\u1ea7n \u0111\u01b0\u1ee3c ki\u1ec3m so\u00e1t ch\u1eb7t ch\u1ebd.<\/strong><\/strong><\/p>\n\n\n\n

b. \u0110i\u1ec1u ch\u1ec9nh k\u1ebft c\u1ea5u kim lo\u1ea1i m\u1ed1i h\u00e0n. Pha \u03b4 trong m\u1ed1i h\u00e0n c\u00f3 th\u1ec3 tinh ch\u1ec9nh k\u00edch th\u01b0\u1edbc h\u1ea1t, lo\u1ea1i b\u1ecf t\u00ednh \u0111\u1ecbnh h\u01b0\u1edbng c\u1ee7a austenite m\u1ed9t pha, gi\u1ea3m s\u1ef1 ph\u00e2n t\u00e1ch c\u00e1c t\u1ea1p ch\u1ea5t c\u00f3 h\u1ea1i trong ranh gi\u1edbi h\u1ea1t v\u00e0 pha \u03b4 c\u00f3 th\u1ec3 h\u00f2a tan nhi\u1ec1u s v\u00e0 P h\u01a1n, l\u00e0m gi\u1ea3m n\u0103ng l\u01b0\u1ee3ng giao di\u1ec7n v\u00e0 h\u00ecnh th\u00e0nh m\u00e0ng ch\u1ea5t l\u1ecfng gi\u1eefa c\u00e1c h\u1ea1t.<\/strong><\/strong><\/p>\n\n\n\n

c. \u0110i\u1ec1u ch\u1ec9nh th\u00e0nh ph\u1ea7n h\u1ee3p kim kim lo\u1ea1i m\u1ed1i h\u00e0n. \u0110\u1ed9 nh\u1ea1y v\u1edbi v\u1ebft n\u1ee9t n\u00f3ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c gi\u1ea3m b\u1eb1ng c\u00e1ch th\u00eam Mn, C, N v\u00e0 c\u00e1c nguy\u00ean t\u1ed1 vi l\u01b0\u1ee3ng nh\u01b0 xeri, cu\u1ed1c v\u00e0 tantalum v\u00e0o th\u00e9p austenit m\u1ed9t pha.<\/strong><\/strong><\/p>\n\n\n\n

d. C\u00e1c bi\u1ec7n ph\u00e1p x\u1eed l\u00fd \u0110\u1ec3 ng\u0103n ch\u1eb7n s\u1ef1 h\u00ecnh th\u00e0nh c\u00e1c h\u1ea1t c\u1ed9t th\u00f4, n\u00ean s\u1eed d\u1ee5ng \u0111\u1ea7u v\u00e0o nhi\u1ec7t nh\u1ecf v\u00e0 h\u1ea1t h\u00e0n c\u00f3 ti\u1ebft di\u1ec7n nh\u1ecf.<\/strong><\/strong><\/p>\n\n\n\n

V\u00ed d\u1ee5, th\u00e9p austenit 25-20 d\u1ec5 b\u1ecb n\u1ee9t h\u00f3a l\u1ecfng. B\u1eb1ng c\u00e1ch h\u1ea1n ch\u1ebf nghi\u00eam ng\u1eb7t h\u00e0m l\u01b0\u1ee3ng t\u1ea1p ch\u1ea5t v\u00e0 k\u00edch th\u01b0\u1edbc h\u1ea1t c\u1ee7a kim lo\u1ea1i c\u01a1 b\u1ea3n, \u00e1p d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p h\u00e0n m\u1eadt \u0111\u1ed9 n\u0103ng l\u01b0\u1ee3ng cao, n\u0103ng l\u01b0\u1ee3ng \u0111\u01b0\u1eddng d\u00e2y nh\u1ecf v\u00e0 t\u0103ng t\u1ed1c \u0111\u1ed9 l\u00e0m m\u00e1t c\u1ee7a m\u1ed1i n\u1ed1i, v.v.<\/strong><\/strong><\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

\u0110\u1ed9 gi\u00f2n c\u1ee7a m\u1ed1i h\u00e0n<\/h2>\n\n\n\n

\u0110\u1ed9 d\u1ebbo c\u1ee7a m\u1ed1i h\u00e0n ph\u1ea3i \u0111\u01b0\u1ee3c \u0111\u1ea3m b\u1ea3o \u0111\u1ed1i v\u1edbi th\u00e9p c\u01b0\u1eddng \u0111\u1ed9 n\u00f3ng \u0111\u1ec3 tr\u00e1nh hi\u1ec7n t\u01b0\u1ee3ng gi\u00f2n \u1edf nhi\u1ec7t \u0111\u1ed9 cao; Th\u00e9p nhi\u1ec7t \u0111\u1ed9 th\u1ea5p ph\u1ea3i c\u00f3 \u0111\u1ed9 b\u1ec1n nhi\u1ec7t \u0111\u1ed9 th\u1ea5p t\u1ed1t \u0111\u1ec3 ng\u0103n ch\u1eb7n hi\u1ec7n t\u01b0\u1ee3ng g\u00e3y gi\u00f2n c\u1ee7a m\u1ed1i h\u00e0n \u1edf nhi\u1ec7t \u0111\u1ed9 th\u1ea5p.<\/strong><\/strong><\/p>\n\n\n\n

Bi\u1ebfn d\u1ea1ng h\u00e0n l\u1edbn<\/h2>\n\n\n\n

Do \u0111\u1ed9 d\u1eabn nhi\u1ec7t th\u1ea5p v\u00e0 h\u1ec7 s\u1ed1 gi\u00e3n n\u1edf l\u1edbn n\u00ean bi\u1ebfn d\u1ea1ng h\u00e0n l\u1edbn n\u00ean c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng v\u1eadt c\u1ed1 \u0111\u1ecbnh \u0111\u1ec3 ng\u0103n ng\u1eeba bi\u1ebfn d\u1ea1ng. L\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p h\u00e0n v\u00e0 v\u1eadt li\u1ec7u h\u00e0n cho th\u00e9p kh\u00f4ng g\u1ec9 austenit: Th\u00e9p kh\u00f4ng g\u1ec9 austenit c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c h\u00e0n b\u1eb1ng TIG, MIG, paw v\u00e0 saw.<\/strong><\/strong><\/p>\n\n\n\n

D\u00f2ng h\u00e0n c\u1ee7a th\u00e9p kh\u00f4ng g\u1ec9 austenit nh\u1ecf v\u00ec \u0111i\u1ec3m n\u00f3ng ch\u1ea3y th\u1ea5p, \u0111\u1ed9 d\u1eabn nhi\u1ec7t nh\u1ecf v\u00e0 h\u1ec7 s\u1ed1 \u0111i\u1ec7n tr\u1edf cao. N\u00ean s\u1eed d\u1ee5ng m\u1ed1i h\u00e0n h\u1eb9p v\u00e0 \u0111\u01b0\u1eddng chuy\u1ec1n h\u1eb9p \u0111\u1ec3 gi\u1ea3m th\u1eddi gian l\u01b0u tr\u00fa \u1edf nhi\u1ec7t \u0111\u1ed9 cao, ng\u0103n ng\u1eeba k\u1ebft t\u1ee7a cacbua, gi\u1ea3m \u1ee9ng su\u1ea5t co ng\u00f3t c\u1ee7a m\u1ed1i h\u00e0n v\u00e0 gi\u1ea3m \u0111\u1ed9 nh\u1ea1y v\u1ebft n\u1ee9t n\u00f3ng.<\/strong><\/strong><\/p>\n\n\n\n

Th\u00e0nh ph\u1ea7n c\u1ee7a v\u1eadt li\u1ec7u h\u00e0n, \u0111\u1eb7c bi\u1ec7t l\u00e0 Cr v\u00e0 Ni, cao h\u01a1n kim lo\u1ea1i c\u01a1 b\u1ea3n. V\u1eadt li\u1ec7u h\u00e0n c\u00f3 ch\u1ee9a m\u1ed9t l\u01b0\u1ee3ng nh\u1ecf ferit (4-12%) \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o kh\u1ea3 n\u0103ng ch\u1ed1ng n\u1ee9t t\u1ed1t (n\u1ee9t l\u1ea1nh, n\u1ee9t n\u00f3ng v\u00e0 n\u1ee9t \u0103n m\u00f2n \u1ee9ng su\u1ea5t) c\u1ee7a m\u1ed1i h\u00e0n.<\/strong><\/strong><\/p>\n\n\n\n

Khi pha ferit kh\u00f4ng \u0111\u01b0\u1ee3c ph\u00e9p ho\u1eb7c kh\u00f4ng th\u1ec3 t\u1ed3n t\u1ea1i trong m\u1ed1i h\u00e0n th\u00ec n\u00ean ch\u1ecdn v\u1eadt li\u1ec7u h\u00e0n ch\u1ee9a Mo, Mn v\u00e0 c\u00e1c nguy\u00ean t\u1ed1 h\u1ee3p kim kh\u00e1c.<\/strong><\/strong><\/p>\n\n\n\n

C, s, P, Si v\u00e0 Nb trong v\u1eadt li\u1ec7u h\u00e0n ph\u1ea3i c\u00e0ng th\u1ea5p c\u00e0ng t\u1ed1t. NB c\u00f3 th\u1ec3 g\u00e2y ra c\u00e1c v\u1ebft n\u1ee9t \u0111\u00f4ng \u0111\u1eb7c trong m\u1ed1i h\u00e0n austenite nguy\u00ean ch\u1ea5t, nh\u01b0ng c\u00f3 th\u1ec3 tr\u00e1nh \u0111\u01b0\u1ee3c m\u1ed9t l\u01b0\u1ee3ng nh\u1ecf ferit trong m\u1ed1i h\u00e0n m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/strong><\/strong><\/p>\n\n\n\n

V\u1eadt li\u1ec7u h\u00e0n ch\u1ee9a Nb th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng cho c\u00e1c k\u1ebft c\u1ea5u h\u00e0n c\u1ea7n \u1ed5n \u0111\u1ecbnh ho\u1eb7c gi\u1ea3m \u1ee9ng su\u1ea5t sau khi h\u00e0n. Khi h\u00e0n h\u1ed3 quang ch\u00ecm \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 h\u00e0n t\u1ea5m trung b\u00ecnh, t\u1ed5n th\u1ea5t ch\u00e1y c\u1ee7a Cr v\u00e0 Ni c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c b\u1ed5 sung b\u1eb1ng s\u1ef1 chuy\u1ec3n ti\u1ebfp c\u1ee7a c\u00e1c nguy\u00ean t\u1ed1 h\u1ee3p kim trong ch\u1ea5t tr\u1ee3 dung v\u00e0 d\u00e2y h\u00e0n;<\/strong><\/strong><\/p>\n\n\n\n

Do \u0111\u1ed9 ng\u1ea5u s\u00e2u n\u00ean c\u1ea7n ch\u00fa \u00fd tr\u00e1nh h\u00ecnh th\u00e0nh c\u00e1c v\u1ebft n\u1ee9t n\u00f3ng \u1edf v\u00f9ng trung t\u00e2m m\u1ed1i h\u00e0n v\u00e0 l\u00e0m gi\u1ea3m kh\u1ea3 n\u0103ng ch\u1ed1ng \u0103n m\u00f2n \u1edf v\u00f9ng ch\u1ecbu \u1ea3nh h\u01b0\u1edfng nhi\u1ec7t. C\u1ea7n ch\u00fa \u00fd l\u1ef1a ch\u1ecdn d\u00e2y h\u00e0n m\u1ecfng h\u01a1n v\u00e0 n\u0103ng l\u01b0\u1ee3ng d\u00e2y h\u00e0n nh\u1ecf h\u01a1n. D\u00e2y h\u00e0n ph\u1ea3i c\u00f3 h\u00e0m l\u01b0\u1ee3ng Si, s v\u00e0 P th\u1ea5p.<\/strong><\/strong><\/p>\n\n\n\n

H\u00e0m l\u01b0\u1ee3ng ferit trong m\u1ed1i h\u00e0n inox ch\u1ecbu nhi\u1ec7t kh\u00f4ng \u0111\u01b0\u1ee3c l\u1edbn h\u01a1n 5%. \u0110\u1ed1i v\u1edbi th\u00e9p kh\u00f4ng g\u1ec9 austenit c\u00f3 h\u01a1n 20% Cr v\u00e0 Ni, n\u00ean ch\u1ecdn d\u00e2y h\u00e0n c\u00f3 Mn cao (6-8%) v\u00e0 ch\u1ea5t tr\u1ee3 dung ki\u1ec1m ho\u1eb7c trung t\u00ednh \u0111\u1ec3 ng\u0103n ch\u1eb7n vi\u1ec7c b\u1ed5 sung Si v\u00e0o m\u1ed1i h\u00e0n v\u00e0 c\u1ea3i thi\u1ec7n kh\u1ea3 n\u0103ng ch\u1ed1ng n\u1ee9t c\u1ee7a n\u00f3.<\/strong><\/strong><\/p>\n\n\n\n

Ch\u1ea5t tr\u1ee3 dung \u0111\u1eb7c bi\u1ec7t cho th\u00e9p kh\u00f4ng g\u1ec9 austenit l\u00e0m t\u0103ng \u00edt Si, c\u00f3 th\u1ec3 chuy\u1ec3n h\u1ee3p kim sang m\u1ed1i h\u00e0n v\u00e0 b\u00f9 \u0111\u1eafp t\u1ed5n th\u1ea5t do \u0111\u1ed1t ch\u00e1y c\u1ee7a c\u00e1c nguy\u00ean t\u1ed1 h\u1ee3p kim \u0111\u1ec3 \u0111\u00e1p \u1ee9ng y\u00eau c\u1ea7u v\u1ec1 t\u00ednh n\u0103ng m\u1ed1i h\u00e0n v\u00e0 th\u00e0nh ph\u1ea7n h\u00f3a h\u1ecdc.<\/strong><\/p>\n\n\n\n

\"\"<\/figure>\n<\/div>","protected":false},"excerpt":{"rendered":"

The welding characteristics of austenitic stainless steel: the elastic and plastic stress and strain are very large in the welding process, but there are few cold cracks. There is no quenching hardening zone and grain coarsening in welded joint, so the tensile strength of weld is high. The main problems of austenitic stainless steel welding…<\/p>","protected":false},"author":2,"featured_media":20223,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[79],"tags":[],"jetpack_featured_media_url":"https:\/\/www.meetyoucarbide.com\/wp-content\/uploads\/2020\/12\/\u56fe\u72477-1.png","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts\/20221"}],"collection":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/comments?post=20221"}],"version-history":[{"count":0,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts\/20221\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/media\/20223"}],"wp:attachment":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/media?parent=20221"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/categories?post=20221"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/tags?post=20221"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}