[[TitleIndustry]]

Cov ntawv thov ntawm Duplex Stainless Steel

Date:Jun 14, 2019

3RE60 (00Cr18Ni8Mo3Si2) yog austenitic-ferritic duplex stainless hlau. Qee qhov chaw ua haujlwm txawv teb siv cov hlau tsis xeb hlau no rau sab hauv ntawm cov yees, xws li grilles, cov tais, thiab lwm yam. Ntu kev faib tawm ntawm cov niam cawv cawv distillation kem, tab sis tom qab kev ua haujlwm, kev ntxhov siab corrosion crack tshwm sim. Tom qab kuaj xyuas thiab tshuaj xyuas, qhov chaw muaj kev nyuaj siab corrosion yog nyob ntawm qhov kub tshaj plaws. Txawm hais tias duplex stainless hlau muaj qhov zoo dua rau kev sib kis intergranular dua li austenitic stainless hlau nrog sib piv cov ntsiab lus carbon, qhov tsis kam rau chloride kev nyuaj siab corrosion ntawm duplex stainless hlau yog qis dua qhov uas zoo li 18-8 austenitic stainless hlau tsuas yog nyob hauv qis kev ntxhov siab. Nws qhia tau tias qee qhov kev ua tau zoo, thiab qhov sib txawv tsis yog loj los yog ib qho zoo tib yam nyob rau hauv kev ua ntawm qhov kev ntxhov siab siab. Yog li ntawd, leej niam cov kua distillation kem ua los ntawm cov khoom siv no tau tawg ntawm phab ntsa ntawm tus pej thuam tom qab 2 xyoo ntawm kev siv, thiab xau tshwm sim.

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Tom qab 5 xyoo ntawm kev siv, muaj ntau tshaj 30 qhov xau nyob hauv txhua tus pej thuam. Kev tawg thiab tawg tshwm sim hauv qhov chaw weld thiab qhov kub-cuam tshuam ntawm thaj chaw ntawm ntauwd lub cev. Ntawm lawv, cov kab nrib pleb hauv thaj chaw muaj cua sov ntawm lub nplhaib weld yog qhov ntau, thiab cov kab nrib pleev hauv thaj chaw loj yog sab nraud radial, uas ua rau cov tawm sab hauv thiab sab nraud. Cov kab nrib pleb hauv cov tshav kub cuam tshuam ntawm thaj chaw ntawm lub weld yog feeb meej. Parallel mus rau weld thiab qhov ntev sib phim rau nws, hauv zos lub tog raj kheej hauv paus cov khoom yog pitting corrosion nyob rau ntau qhov chaw. Cov laj thawj rau kev tsom xam yog tias qhov kev ntxhov siab no feem ntau yog los ntawm qhov kev ntxhov siab xeb kev puas tsuaj ntawm chloride. Qhov ua kom muaj kev cuam tshuam los ntawm kev nyuaj siab corrosion tawg yog feem ntau vuam kev nyuaj siab, tshwj xeeb tshaj yog cov kev ntxhov siab los ntawm cov kev ntxhov siab vim los ntawm kev kho lub vuam thiab cov qauv kev nyuaj siab tsim tawm thaum lub sijhawm tsim khoom siv. Kev ntsuas thiab ziab ntawm phab ntsa ntawm tus pej thuam hloov siab ua rau muaj cov tshuaj chloride ion nruab nrab kom ua rau kev nyuaj siab corrosion. Thaum kawg, nws xaus lus tias duplex stainless hlau tsis tuaj yeem tiv thaiv cov kev mob ntawm cov dej cawv cawv hauv tsob nroj alkali. Rau kev thov cov khoom siv hauv cov dej qab zib tshauv, qhov kub siab pom zoo yuav tsum tsis tshaj 80 ° C, thiab kev saib xyuas yuav tsum them kom tsis txhob muaj kev ntxhov siab thaum lub sijhawm tsim thiab tsim khoom. Qhov no tseem qhia tau tias hauv kev lag luam kev lag luam, kev xaiv ntawm cov khoom tsim nyog yog qhov tseem ceeb tshaj plaws rau kev nyab xeeb, kev ruaj khov thiab txo nqi ntawm ntau lawm.

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Cov tshuaj tiv thaiv corrosion ntawm stainless hlau yog feem ntau ua tiav los ntawm kev hla ntawm Fe-Cr alloy. Zaj duab xis passivation ntawm stainless hlau yog tsis tshua muaj nyias, txog 1-10 nm, zaj duab xis tsis yog yam tsis xws luag, thiab lub zos ib txwm yog qhov tsis xws luag. Yog li ntawd, zaj duab xis passivation yog qhov yooj yim. Kev tsim txom los ntawm kev puas tsuaj, xws li tshuaj lom neeg thiab kev puas tsuaj rau lub tshuab, kev siv tshuaj lom neeg ntawm kev ua yeeb yaj kiab passivation yog vim muaj kev sib cuam tshuam ntawm kev ua yeeb yam qias neeg xws li chloride thiab passivation zaj duab xis, uas ua rau hauv zos ua rau corrosion xws li pitting, crevice corrosion thiab intergranular corrosion. Cov.

Raws li rau lub tshuab ntawm kev puas tsuaj rau zaj duab xis passivation xws li chloride ions, nws kuj tseem muaj teeb meem tshawb nrhiav. Cov neeg kho tshuab kev puas tsuaj ntawm zaj duab xis passivation yog qhov tshwm sim ntawm kev sib txuam ntawm qhov kev hloov kho thiab lub zog quab yuam. Hauv daim ntawv no ua tsis tiav, lub halide ion ua lub luag haujlwm tseem ceeb, yog li nws tseem ceeb heev los xaiv cov khoom haum rau cov kev ua haujlwm txawv.


Tug: Daim ntawv thov ntawm stainless hlau hauv cov qauv

Tom ntej: Dab tsi yog austenite stainless hlau: