Weldability ntawm cov ntaub ntawv hlau yog hais txog lub peev xwm ntawm cov ntaub ntawv hlau kom tau txais kev sib txuas zoo heev siv cov txheej txheem vuam, nrog rau cov txheej txheem vuam, cov khoom siv vuam, vuam specifications thiab vuam cov qauv.Yog tias cov hlau tuaj yeem tau txais kev sib txuas zoo heev siv cov txheej txheem vuam ntau dua thiab yooj yim, nws tau txiav txim siab tias muaj kev vuam zoo.Weldability ntawm cov ntaub ntawv hlau feem ntau muab faib ua ob yam: txheej txheem weldability thiab daim ntawv thov weldability.
Txheej txheem weldability: hais txog lub peev xwm kom tau txais txiaj ntsig zoo, tsis muaj qhov tsis xws luag welded pob qij txha nyob rau hauv qee yam txheej txheem vuam.Nws tsis yog cov cuab yeej cuab tam ntawm cov hlau, tab sis raug soj ntsuam raws li ib txoj kev vuam thiab cov txheej txheem tshwj xeeb uas siv.Yog li ntawd, cov txheej txheem weldability ntawm cov ntaub ntawv hlau yog ze ze rau cov txheej txheem vuam.
Kev pabcuam weldability: hais txog qib uas cov welded sib koom ua ke los yog tag nrho cov qauv ua tau raws li qhov kev pabcuam kev ua haujlwm tau teev tseg los ntawm cov khoom siv khoom.Qhov kev ua tau zoo nyob ntawm kev ua haujlwm ntawm cov qauv welded thiab cov kev xav tau muab tso rau hauv kev tsim.Feem ntau suav nrog cov khoom siv hluav taws xob, tsis muaj qhov kub thiab txias tsis kam, nkig tawg tsis kam, siab kub creep, qaug zog, lub zog ntev, corrosion kuj thiab hnav tsis kam, thiab lwm yam. Piv txwv li, feem ntau siv S30403 thiab S31603 stainless hlau muaj corrosion kuj zoo heev, thiab 16MnDR. thiab 09MnNiDR cov hlau tsis tshua muaj kub kuj tseem muaj qhov kub thiab txias toughness tsis kam.
Cov yam ntxwv cuam tshuam rau kev ua haujlwm vuam ntawm cov khoom siv hlau
1. Khoom yam ntxwv
Cov ntaub ntawv muaj xws li cov hlau thiab cov khoom siv vuam.Nyob rau hauv tib lub welding tej yam kev mob, lub ntsiab yam tseem ceeb uas txiav txim lub weldability ntawm lub hauv paus hlau yog nws lub cev khoom thiab tshuaj muaj pes tsawg leeg.
Nyob rau hauv cov nqe lus ntawm lub cev khoom: yam xws li lub melting point, thermal conductivity, linear expansion coefficient, ceev, tshav kub muaj peev xwm thiab lwm yam tseem ceeb ntawm cov hlau tag nrho cov muaj feem xyuam rau cov txheej txheem xws li thermal voj voog, melting, crystallization, theem hloov, thiab lwm yam. , yog li cuam tshuam rau weldability.Cov ntaub ntawv uas tsis muaj thermal conductivity xws li stainless hlau muaj qhov kub thiab txias gradients, siab residual stress, thiab loj deformation thaum vuam.Tsis tas li ntawd, vim lub sijhawm nyob ntev ntawm qhov kub thiab txias, cov nplej hauv thaj chaw muaj kev kub ntxhov loj tuaj, uas ua rau muaj kev puas tsuaj rau kev sib koom ua ke.Austenitic stainless hlau muaj ib tug loj linear expansion coefficient thiab hnyav sib koom deformation thiab kev ntxhov siab.
Nyob rau hauv cov nqe lus ntawm cov tshuaj muaj pes tsawg leeg, lub feem ntau influential keeb yog carbon, uas txhais tau hais tias cov pa roj carbon ntsiab lus ntawm cov hlau txiav txim nws weldability.Feem ntau ntawm lwm cov alloying ntsiab nyob rau hauv steel tsis haum rau welding, tab sis lawv cov kev cuam tshuam yog feem ntau me dua li cov carbon.Raws li cov ntsiab lus ntawm cov pa roj carbon monoxide hauv cov hlau nce, qhov kev sib tw hardening nce, cov yas txo qis, thiab cov kab nrib pleb tuaj yeem tshwm sim.Feem ntau, qhov rhiab heev ntawm cov ntaub ntawv hlau rau cov kab nrib pleb thaum vuam thiab cov kev hloov hauv cov khoom siv ntawm cov khoom siv sib txuas yog siv los ua cov cim tseem ceeb los ntsuas qhov weldability ntawm cov ntaub ntawv.Yog li ntawd, qhov siab dua cov ntsiab lus ntawm cov pa roj carbon monoxide, qhov phem dua qhov weldability.Cov pa roj carbon tsawg thiab cov hlau tsis tshua muaj hlau nrog cov ntsiab lus ntawm cov pa roj carbon tsawg dua 0.25% muaj cov yas zoo heev thiab muaj kev cuam tshuam zoo, thiab cov yas thiab cuam tshuam rau cov pob qij txha tom qab vuam kuj zoo heev.Kev kho cua sov thiab tom qab vuam tsis tas yuav tsum tau ua thaum vuam, thiab cov txheej txheem vuam yog yooj yim los tswj, yog li nws muaj qhov zoo weldability.
Tsis tas li ntawd, lub smelting thiab dov lub xeev, kev kho cua sov lub xeev, lub koom haum lub xeev, thiab lwm yam ntawm steel tag nrho cov cuam tshuam weldability rau txawv degrees.Lub weldability ntawm steel tuaj yeem txhim kho los ntawm kev ua kom zoo lossis ua kom zoo dua cov nplej thiab tswj cov txheej txheem dov.
Vuam cov ntaub ntawv ncaj qha koom nrog hauv cov tshuaj metallurgical cov tshuaj tiv thaiv thaum lub sij hawm vuam txheej txheem, uas txiav txim siab muaj pes tsawg leeg, qauv, cov khoom thiab qhov tsis xws luag tsim ntawm cov hlau vuam.Yog tias cov khoom siv vuam raug xaiv tsis raug thiab tsis haum rau lub hauv paus hlau, tsis yog tsuas yog ib qho kev sib koom ua tau raws li qhov yuav tsum tau siv, tab sis qhov tsis xws luag xws li tawg thiab kev hloov ntawm cov yam ntxwv ntawm cov khoom yuav raug qhia.Yog li ntawd, kev xaiv kom raug ntawm cov khoom siv vuam yog ib qho tseem ceeb hauv kev ua kom cov pob qij txha zoo.
2. Cov txheej txheem txheej txheem
Cov txheej txheem txheej txheem muaj xws li vuam txoj kev, vuam txheej txheem tsis, vuam ib ntus, preheating, tom qab cua sov thiab tom qab vuam thaum tshav kub kub kho, thiab lwm yam. Cov txheej txheem vuam muaj kev cuam tshuam zoo rau cov weldability, feem ntau nyob rau hauv ob yam: cov yam ntxwv ntawm cov cua sov thiab kev tiv thaiv.
Cov kev sib txawv vuam muaj cov cua sov sib txawv heev, hluav taws xob kub ntau, thiab lwm yam cua sov nyob rau hauv cov khoom sib txawv.Piv txwv li, lub zog ntawm electroslag vuam yog siab heev, tab sis lub zog ntom yog tsawg heev, thiab cua sov siab kawg yog tsis siab.Cov cua sov yog qeeb thaum lub sij hawm vuam, thiab lub sij hawm nyob rau hauv qhov kub thiab txias yog ntev, ua rau cov nplej ntxhib nyob rau hauv lub tshav kub-cuam tshuam cheeb tsam thiab ib tug tseem ceeb txo nyob rau hauv tej yam toughness, uas yuav tsum normalized.Txhim kho.Nyob rau hauv sib piv, electron beam welding, laser welding thiab lwm txoj kev muaj zog tsawg, tab sis siab zog ceev thiab ceev cua sov.Lub sijhawm nyob hauv qhov kub thiab txias yog luv luv, thaj chaw tshav kub cuam tshuam yog nqaim heev, thiab tsis muaj kev phom sij ntawm cov qoob loo loj hlob.
Kho cov txheej txheem welding tsis thiab siv lwm cov txheej txheem ntsuas xws li preheating, postheating, ntau txheej vuam thiab tswj interlayer kub tuaj yeem kho thiab tswj lub vuam thermal voj voog, yog li hloov qhov weldability ntawm cov hlau.Yog tias kev ntsuas xws li preheating ua ntej vuam lossis kev kho cua sov tom qab siv vuam, nws yog qhov ua tau kom tau txais cov pob qij txha welded yam tsis muaj qhov tsis xws luag uas ua tau raws li qhov yuav tsum tau ua.
3. Cov yam ntxwv ntawm cov qauv
Nws tsuas yog hais txog cov qauv tsim ntawm cov qauv welded thiab cov pob qij txha welded, xws li qhov cuam tshuam ntawm cov yam ntxwv xws li cov qauv duab, qhov loj, tuab, daim ntawv sib koom ua ke, vuam txheej txheem thiab nws cov duab ntu ntawm weldability.Nws cov cawv feem ntau yog tshwm sim hauv kev hloov pauv ntawm tshav kub thiab lub xeev ntawm kev quab yuam.Cov phaj thicknesses sib txawv, cov ntawv sib koom sib txawv lossis cov duab zawj muaj qhov sib txawv ntawm cov cua kub hloov ceev cov lus qhia thiab cov nqi, uas yuav cuam tshuam rau cov crystallization kev taw qhia thiab cov qoob loo loj hlob ntawm lub pas dej molten.Cov txheej txheem hloov, phaj thickness thiab weld kev npaj txiav txim siab qhov nruj thiab txwv ntawm kev sib koom tes, uas cuam tshuam rau lub xeev kev ntxhov siab ntawm kev sib koom tes.Tsis zoo siv lead ua morphology, kev ntxhov siab loj heev thiab kev ntxhov siab vuam ntau dhau yog cov xwm txheej yooj yim rau kev tsim cov kab nrib pleb.Hauv kev tsim, txo cov kev sib koom ua ke, txo cov ntoo khaub lig welds, thiab txo ntau yam ua rau muaj kev ntxhov siab yog tag nrho cov kev ntsuas tseem ceeb los txhim kho weldability.
4. Cov xwm txheej ntawm kev siv
Nws yog hais txog kev khiav hauj lwm kub, load tej yam kev mob thiab ua hauj lwm nruab nrab thaum lub sij hawm kev pab cuam ntawm lub welded qauv.Cov chaw ua haujlwm thiab kev ua haujlwm no xav tau cov qauv welded kom muaj kev sib raug zoo.Piv txwv li, cov qauv welded ua haujlwm ntawm qhov kub thiab txias yuav tsum muaj nkig puas;cov qauv ua haujlwm ntawm qhov kub thiab txias yuav tsum muaj kev nkag siab zoo;cov qauv ua haujlwm nyob rau hauv alternating loads yuav tsum muaj kev qaug zog zoo;cov qauv ua haujlwm hauv cov kua qaub, alkali lossis ntsev media Lub thawv welded yuav tsum muaj kev tiv thaiv corrosion siab thiab lwm yam.Hauv luv luv, qhov hnyav dua qhov kev siv, qhov siab dua qhov yuav tsum tau ua rau cov pob qij txha welded, thiab qhov nyuaj nws yog los xyuas kom meej lub weldability ntawm cov khoom.
Kev txheeb xyuas thiab kev ntsuas ntsuas ntawm weldability ntawm cov ntaub ntawv hlau
Thaum lub sij hawm vuam txheej txheem, cov khoom siv vuam thermal txheej txheem, metallurgical cov tshuaj tiv thaiv, nrog rau cov vuam kev nyuaj siab thiab deformation, ua rau muaj kev hloov hauv tshuaj muaj pes tsawg leeg, metallographic qauv, qhov loj thiab cov duab, ua rau kev ua tau zoo ntawm cov welded sib koom ua ke feem ntau sib txawv ntawm cov khoom. cov khoom siv hauv paus, qee zaum txawm tsis tuaj yeem ua tau raws li cov kev cai siv.Rau ntau cov reactive los yog refractory hlau, tshwj xeeb welding txoj kev xws li electron beam welding los yog laser vuam yuav tsum tau siv kom tau cov pob qij txha zoo.Cov khoom siv tsawg dua thiab tsis yooj yim yuav tsum tau ua kom zoo welded sib koom ua ke los ntawm cov khoom siv, qhov zoo dua qhov weldability ntawm cov khoom;ntawm qhov tsis sib xws, yog tias txoj kev vuam nyuaj thiab kim, cov khoom siv vuam tshwj xeeb thiab cov txheej txheem yuav tsum tau ua, nws txhais tau tias cov khoom siv vuam tsis zoo.
Thaum tsim cov khoom lag luam, qhov weldability ntawm cov ntaub ntawv siv yuav tsum tau soj ntsuam ua ntej los txiav txim seb cov khoom siv ntawm cov khoom siv, cov khoom siv vuam, thiab cov txheej txheem vuam puas tsim nyog.Muaj ntau txoj hauv kev los ntsuas qhov weldability ntawm cov ntaub ntawv.Txhua txoj kev tsuas tuaj yeem piav qhia txog qee yam ntawm weldability.Yog li ntawd, kev ntsuam xyuas yuav tsum tau txiav txim siab tag nrho cov weldability.Cov kev sim tuaj yeem muab faib ua hom simulation thiab hom kev sim.Cov qub simulates cua sov thiab txias yam ntxwv ntawm vuam;tom kawg kev xeem raws li qhov tseeb vuam tej yam kev mob.Cov ntsiab lus ntawm kev xeem yog tsuas yog txhawm rau txheeb xyuas cov tshuaj muaj pes tsawg leeg, cov qauv metallographic, cov khoom siv kho tshuab, thiab muaj lossis tsis muaj qhov cuam tshuam ntawm vuam ntawm lub hauv paus hlau thiab vuam hlau, thiab txiav txim siab qhov ntsuas kub qis, kev ua haujlwm siab, corrosion resistance, thiab tawg tsis kam ntawm welded sib koom.
Vuam yam ntxwv ntawm cov khoom siv hlau feem ntau siv
1. Welding ntawm carbon steel
(1) Vuam ntawm cov pa roj carbon tsawg
Tsawg carbon steel muaj cov ntsiab lus carbon tsawg, tsawg manganese thiab silicon cov ntsiab lus.Nyob rau hauv ib txwm muaj xwm txheej, nws yuav tsis ua rau cov txheej txheem hardening loj lossis quenching qauv vim vuam.Cov hlau zoo li no muaj cov yas zoo heev thiab muaj kev cuam tshuam toughness, thiab cov yas thiab toughness ntawm nws cov pob qij txha welded kuj zoo heev.Preheating thiab postheating feem ntau tsis tas yuav tsum tau ua thaum vuam, thiab cov txheej txheem tshwj xeeb tsis tas yuav tsum tau txais cov pob qij txha welded nrog zoo txaus.Yog li ntawd, cov pa roj carbon tsawg muaj qhov zoo tshaj plaws vuam kev ua tau zoo thiab yog cov hlau nrog qhov zoo tshaj plaws vuam kev ua tau zoo ntawm tag nrho cov hlau..
(2) Vuam ntawm nruab nrab carbon steel
Cov pa roj carbon nruab nrab muaj cov ntsiab lus ntawm cov pa roj carbon ntau dua thiab nws cov weldability yog qhov phem dua li cov pa roj carbon tsawg.Thaum CE ze rau qhov qis qis (0.25%), weldability yog qhov zoo.Raws li cov ntsiab lus ntawm cov pa roj carbon monoxide nce, lub hardening nyiam nce, thiab cov qauv qis-plasticity martensite tau yooj yim tsim nyob rau hauv thaj chaw uas muaj kev kub ntxhov.Thaum cov welding tseem nruj los yog cov khoom siv vuam thiab cov txheej txheem tsis raug xaiv, cov kab mob khaub thuas yuav tshwm sim.Thaum welding thawj txheej ntawm ntau txheej vuam, vim qhov loj ntawm lub hauv paus hlau fused rau hauv vuam, cov ntsiab lus carbon, sulfur thiab phosphorus cov ntsiab lus nce, ua rau nws yooj yim los tsim kub tawg.Tsis tas li ntawd, lub cev rhiab heev kuj nce thaum cov ntsiab lus carbon siab.
(3) Welding ntawm high carbon steel
High carbon steel nrog CE ntau dua 0.6% muaj zog hardenability thiab nws yooj yim los tsim nyuaj thiab nkig siab carbon martensite.Kev tawg yooj yim tuaj yeem tshwm sim hauv cov welds thiab thaj chaw muaj kev kub ntxhov, ua rau vuam nyuaj.Yog li ntawd, hom hlau no feem ntau tsis yog siv los ua cov qauv welded, tab sis yog siv los ua cov khoom lossis cov khoom uas muaj siab hardness lossis hnav tsis kam.Feem ntau ntawm lawv cov vuam yog kho qhov puas.Cov khoom thiab cov khoom no yuav tsum tau muab tshem tawm ua ntej vuam kho kom txo tau cov kab nrib pleb, thiab tom qab ntawd rov kho dua tom qab vuam.
2. Vuam uas tsis tshua muaj alloy siab zog steel
Cov pa roj carbon ntsiab lus ntawm cov hlau tsis tshua muaj zog hlau feem ntau tsis tshaj 0.20%, thiab tag nrho cov ntsiab lus alloying feem ntau tsis tshaj 5%.Nws yog qhov tseeb vim tias cov hlau tsis tshua muaj hlau muaj zog muaj qee yam ntawm cov hlau alloy uas nws qhov kev ua haujlwm vuam yog txawv me ntsis ntawm cov hlau.Nws cov yam ntxwv welding yog raws li nram no:
(1) Vuam kab nrib pleb hauv welded pob qij txha
Txias-tawg qis-alloy high-strength steel muaj C, Mn, V, Nb thiab lwm yam uas ntxiv dag zog rau cov hlau, yog li nws yooj yim rau hardened thaum vuam.Cov txheej txheem hardened no yog rhiab heev.Yog li ntawd, thaum lub rigidity loj los yog lub restraining kev nyuaj siab yog siab, yog hais tias tus txheej txheem welding tsis zoo yuav yooj yim ua rau mob khaub thuas.Ntxiv mus, hom kev tawg no muaj qee qhov ncua sij hawm thiab muaj kev phom sij heev.
Reheat (SR) tawg Reheat tawg yog intergranular tawg uas tshwm sim nyob rau hauv lub coarse-grained cheeb tsam nyob ze ntawm lub fusion kab thaum lub sij hawm tom qab-weld kev nyuaj siab relief tshav kub kev kho mob los yog ntev-lub sij hawm ua hauj lwm kub.Nws feem ntau ntseeg tias nws tshwm sim vim qhov kub ntawm vuam ua rau V, Nb, Cr, Mo thiab lwm yam carbides nyob ze ntawm HAZ kom muaj zog yaj hauv austenite.Lawv tsis muaj sij hawm los nag thaum lub sij hawm txias tom qab vuam, tab sis disperse thiab precipitate thaum lub sij hawm PWHT, yog li ntxiv dag zog rau cov qauv siv lead ua.Nyob rau hauv tas li ntawd, lub creep deformation thaum lub sij hawm kev nyuaj siab so yog concentrated nyob rau hauv lub grain ciam teb.
Tsawg-alloy high-strength steel welded pob qij txha feem ntau tsis muaj qhov rov ua kom tawg, xws li 16MnR, 15MnVR, thiab lwm yam. Txawm li cas los xij, rau Mn-Mo-Nb thiab Mn-Mo-V series low-alloy high-strength steels, xws li 07MnCrMoVR, txij li Nb, V, thiab Mo yog cov ntsiab lus uas muaj zog rhiab heev rau reheat cracking, hom hlau no yuav tsum tau kho thaum lub sij hawm tom qab vuam kub kho.Kev saib xyuas yuav tsum tau ua kom tsis txhob muaj qhov kub thiab txias ntawm qhov chaw reheat tawg kom tiv thaiv qhov tshwm sim ntawm reheat tawg.
(2) Embrittlement thiab softening ntawm welded pob qij txha
Kev laus embrittlement Welded pob qij txha yuav tsum tau ua ntau yam txheej txheem txias (dawb shearing, chim dov, thiab lwm yam) ua ntej welding.Cov hlau yuav tsim cov yas deformation.Yog hais tias thaj chaw yog rhuab mus rau 200 mus rau 450 ° C, strain aging yuav tshwm sim..Strain aging embrittlement yuav txo cov yas ntawm cov hlau thiab ua rau kom qhov kub thiab txias hloov, uas ua rau cov khoom tawg yooj yim.Kev kho cua sov tom qab vuam tuaj yeem tshem tawm xws li kev laus ntawm cov qauv welded thiab rov ua kom tawv.
Embrittlement ntawm welds thiab tshav kub-tshwj xeeb zones Vuam yog ib qho kev tsis sib xws ntawm cov cua sov thiab cua txias, uas ua rau cov qauv tsis sib xws.Qhov kev hloov pauv ntawm qhov kub thiab txias ntawm qhov vuam (WM) thiab tshav kub-cuam tshuam cheeb tsam (HAZ) yog siab dua li ntawm cov hlau puag thiab yog qhov tsis muaj zog ntawm qhov sib txuas.Vuam kab hluav taws xob muaj qhov cuam tshuam tseem ceeb rau cov khoom ntawm cov khoom siv qis-alloy high-strength steel WM thiab HAZ.Tsawg-alloy high-strength steel yog yooj yim rau harden.Yog tias cov kab hluav taws xob tsawg dhau, martensite yuav tshwm sim hauv HAZ thiab ua rau tawg.Yog tias cov kab hluav taws xob loj dhau lawm, cov nplej ntawm WM thiab HAZ yuav dhau los ua ntxhib.Yuav ua rau kev sib koom ua nkig.Piv nrog cov kub-kuav los tiag thiab cov hlau tsis zoo, cov pa roj carbon tsawg thiab tempered steel muaj qhov hnyav dua rau HAZ embrittlement tshwm sim los ntawm ntau lub zog linear.Yog li ntawd, thaum welding, cov kab hluav taws xob yuav tsum raug txwv rau qee yam.
Softening ntawm tshav kub-cuam tshuam cheeb tsam ntawm welded pob qij txha Vim qhov kev txiav txim ntawm vuam tshav kub, sab nraum lub tshav kub-cuam tshuam cheeb tsam (HAZ) ntawm tsawg-carbon quenched thiab tempered steel yog rhuab saum lub tempering kub, tshwj xeeb tshaj yog thaj tsam ze ntawm Ac1, uas yuav tsim ib thaj chaw softening nrog txo lub zog.Cov txheej txheem softening nyob rau hauv cheeb tsam HAZ nce nrog nce nyob rau hauv vuam kab zog thiab preheating kub, tab sis feem ntau lub tensile zog nyob rau hauv lub softened cheeb tsam yog tseem siab tshaj qhov qis tshaj ntawm tus qauv tus nqi ntawm lub hauv paus hlau, yog li lub tshav kub cuam tshuam cheeb tsam. ntawm hom hlau no softens Raws li ntev raws li kev ua haujlwm zoo, qhov teeb meem yuav tsis cuam tshuam rau kev ua haujlwm ntawm kev sib koom tes.
3. Vuam ntawm stainless hlau
Stainless hlau tuaj yeem muab faib ua plaub pawg raws li nws cov qauv hlau sib txawv, xws li austenitic stainless hlau, ferritic stainless hlau, martensitic stainless hlau, thiab austenitic-ferritic duplex stainless hlau.Cov hauv qab no feem ntau txheeb xyuas cov yam ntxwv vuam ntawm austenitic stainless hlau thiab bidirectional stainless hlau.
(1) Welding ntawm austenitic stainless hlau
Austenitic stainless hlau yog yooj yim rau weld dua li lwm yam stainless hlau.Yuav tsis muaj theem hloov pauv ntawm qhov kub thiab txias thiab nws tsis nkag siab rau hydrogen embrittlement.Lub austenitic stainless hlau sib koom ua ke kuj muaj zoo plasticity thiab toughness nyob rau hauv lub xeev welded.Cov teeb meem tseem ceeb ntawm kev vuam yog: vuam kub tawg, embrittlement, intergranular corrosion thiab kev nyuaj siab corrosion, thiab lwm yam, vim tsis zoo thermal conductivity thiab loj linear expansion coefficient, vuam kev nyuaj siab thiab deformation yog loj.Thaum welding, vuam cua sov input yuav tsum tsawg li tsawg tau, thiab yuav tsum tsis muaj preheating, thiab interlayer kub yuav tsum tau txo.Lub interlayer kub yuav tsum tau tswj hauv qab 60 ° C, thiab cov pob qij txha yuav tsum staggered.Txhawm rau txo cov cua sov, qhov vuam ceev yuav tsum tsis txhob nce ntau dhau, tab sis cov vuam tam sim no yuav tsum raug txo kom tsim nyog.
(2) Vuam ntawm austenitic-ferritic ob txoj kev stainless hlau
Austenitic-ferritic duplex stainless hlau yog duplex stainless hlau muaj ob theem: austenite thiab ferrite.Nws muab cov txiaj ntsig zoo ntawm austenitic steel thiab ferritic steel, yog li nws muaj cov yam ntxwv ntawm lub zog siab, zoo corrosion kuj thiab yooj yim vuam.Tam sim no, muaj peb yam tseem ceeb ntawm duplex stainless hlau: Cr18, Cr21, thiab Cr25.Cov yam ntxwv tseem ceeb ntawm hom hlau vuam no yog: qis thermal nyiam piv nrog austenitic stainless hlau;qis embrittlement nyiam tom qab vuam piv nrog cov ntshiab ferritic stainless hlau, thiab cov degree ntawm ferrite coarsening nyob rau hauv vuam kub cuam tshuam cheeb tsam Nws kuj yog qis dua, yog li cov weldability zoo dua.
Txij li cov hlau no muaj cov khoom siv vuam zoo, preheating thiab postheating tsis tas yuav tsum tau ua thaum vuam.Nyias daim hlau yuav tsum tau welded los ntawm TIG, thiab nruab nrab thiab tuab daim hlau yuav welded los ntawm arc vuam.Thaum vuam los ntawm arc vuam, tshwj xeeb vuam pas nrig nrog zoo sib xws rau lub hauv paus hlau los yog austenitic vuam rods uas muaj cov ntsiab lus carbon tsawg yuav tsum tau siv.Nickel-based alloy electrodes kuj tseem siv tau rau Cr25 hom dual-theem steel.
Dual-theem steels muaj ib tug loj feem ntawm ferrite, thiab inherent embrittlement tendencies ntawm ferritic steels, xws li brittleness ntawm 475 ° C, σ theem nag lossis daus embrittlement thiab coarse nplej, tseem muaj nyob, tsuas yog vim muaj cov austenite.Qee qhov kev nyem tuaj yeem tau txais los ntawm qhov sib npaug, tab sis koj tseem yuav tsum tau ua tib zoo saib thaum vuam.Thaum vuam Ni-dawb los yog tsawg-Ni duplex stainless hlau, muaj ib tug nyiam rau ib-theem ferrite thiab grain coarsening nyob rau hauv lub tshav kub-cuam tshuam cheeb tsam.Lub sijhawm no, kev saib xyuas yuav tsum tau them nyiaj rau kev tswj cov vuam cua sov tawm tswv yim, thiab sim siv me me tam sim no, vuam ceev ceev, thiab nqaim channel vuam.Thiab multi-pass welding los tiv thaiv grain coarsening thiab ib-theem ferriteization nyob rau hauv tshav kub-cuam tshuam cheeb tsam.Qhov nruab nrab txheej kub yuav tsum tsis txhob siab dhau.Nws yog qhov zoo tshaj rau weld qhov txuas ntxiv tom qab txias.
Post lub sij hawm: Sep-11-2023