Nyob rau hauv lub realm ntawm cov ntaub ntawv niaj hnub, stainless hlau sawv ua ib tus paragon ntawm durability thiab kev ua haujlwm, muaj nuj nqi rau nws qhov zoo siab mus rau corrosion. Cov cuab yeej tshwj xeeb no tau muab cov khoom siv hlau tsis muaj hluav taws xob tsis muaj kev lag luam muaj ntau yam hauv chav ua noj, hauv chav ua noj thiab kos duab rau Aerospace thiab cov khoom siv kho mob. Tab sis dab tsi raws nraim cov lus dag tom qab nws muaj peev xwm tshwj xeeb los tiv thaiv kev puas xeb thiab kev txwv? Cia li pib taug kev los tshawb txog cov ntsiab cai science uas tau txais txiaj ntsig stainless hlau nrog nws corrosion-resistant prwess.
Ntawm lub plawv ntawm stainless hlau lub corrosion tsis kam yog nws muaj pes tsawg leeg. Stainless hlau yog ib qho alloy feem tsim ntawm cov hlau, nrog ntxiv ntawm lwm cov ntsiab lus, feem ntau cov chromium feem ntau. Qhov tsawg kawg nkaus cov ntsiab lus chromium tsawg kawg nkaus hauv stainless hlau feem ntau yog 10.5%, ib qhov tseem ceeb ntawm qhov pib uas pib cov txheej txheem tshuaj pauv hluav taws xob. Thaum chromium tuaj rau hauv kev sib cuag nrog oxygen nyob rau huab cua lossis noo noo, nws sai sai txheej, thiab nruj nreem txheej ntawm chromium oxide nyob rau saum npoo ntawm cov hlau. Qhov no cov txheej chromium oxide, feem ntau hu ua cov duab sib dhos, ua kom tiv thaiv cov hlau nkawv, tiv thaiv cov hlau oxide, feem ntau yog hu ua cov xeb.
Zaj duab xis passive kev tiv thaiv kev tiv thaiv yog qhov ua tau zoo thiab kho tus kheej. Txawm hais tias qhov saum npoo ntawm cov hlau tsis xeb yog khawb lossis puas, cov chromium nyob rau hauv alloy nrawm nrawm nrawm. Qhov no tus kheej kho cov khoom ntiag tug stainless hlau cais tawm los ntawm ntau yam hlau thiab alloys, ua rau nws ntseeg tau nyob rau hauv ntau qhov chaw ib puag ncig.
Ntxiv rau cov chromium, lwm cov ntsiab lus ntxiv rau stainless hlau kuj tseem tuaj yeem txhim kho nws corrosion tsis kam. Nickel, piv txwv li, txhim kho cov hlau ua kom tsis kam rau corrosion hauv cov acidic ib puag ncig thiab nce nws cov ductilit
Thiab kev nruj heev. Molybdenum txuas ntxiv txhim kho cov corrosion tsis kam nyob rau hauv cov xwm txheej hnyav, xws li cov uas muaj cov txheej txheem ntau chloride, uas feem ntau pom nyob hauv dej hiav txwv thiab qee cov txheej txheem muaj. Cov ntsiab lus ntxiv ua haujlwm hauv kev hais kwv txhiaj nrog chromium los tsim cov qauv alloy loj uas muaj kev tiv thaiv zoo tshaj plaws tiv thaiv ntau yam ntawm cov neeg sawv cev.
Lub microstructure ntawm stainless hlau tseem ua lub luag haujlwm tseem ceeb hauv nws cov xeb tsis kam. Ntau yam ntawm cov hlau stainless, xws li Austenitic, Ferritic, martensitic, thiab duplex, muaj cov qauv microstructures uas cuam tshuam rau lawv cov kev coj ua kom haum. Austenitic stainless hlau, uas muaj feem pua ntawm npib tsib ntawm npib tsib xee thiab chromium, feem ntau yog tiv taus corrosion vim lawv cov khaub ncaws hnav, tsis sib nqus microstructure. Cov hlau ferritic sterritic, ntawm qhov tod tes, muaj cov ntsiab lus tsib xee thiab muaj kev sib nqus microscepture, muab ntau qhov kev sib nqus me me rau pitting thiab crevice corrosion nyob rau hauv cov neeg mob hnyav. Nkag siab txog kev sib raug zoo ntawm microstructure thiab corrosion kuj tseem ceeb rau kev xaiv cov hlau uas tsim nyog rau cov kev siv tshwj xeeb.
Ntxiv mus, ib puag ncig cov kev cuam tshuam tseem ceeb cuam tshuam rau corrosion tsis kam ntawm cov hlau stainless. Qhov kub, av noo, muaj cov tshuaj muaj kev txhoj puab heev, thiab Ph Phaj nruab nrab txhua qhov cuam tshuam tus nqi ntawm corrosion tshwm sim. Nyob rau hauv high-humity lossis marine ib puag ncig, piv txwv li, kev pheej hmoo ntawm chloride-ntxias pitting corrosion nce. Txhawm rau txo qhov no, stainless hlau nrog ntau dua Molybdenum thiab chromium cov ntsiab lus feem ntau xaiv. Ib yam li ntawd, hauv cov acidic lossis alkaline ib puag ncig, cov tshuaj lom neeg tshwj xeeb ntawm cov hlau stainless yuav tsum tau ua tib zoo xaiv kom ntseeg tau qhov zoo corrosion.
Thaum muab piv rau lwm cov hlau uas muaj ntau yam xws li cov hlau hlau, qhov sib txawv hauv kev ua xeb yog stark. Carbon hlau, uas tsis muaj cov txheej txheem tiv thaiv cov roj ntsha oxide, yooj yim corrodes thaum raug rau huab cua thiab ya raws. Cov ntaub ntawv xeb sai sai rau nws cov npoo av, tsis muaj zog cov khoom raws sijhawm. Nyob rau hauv kev sib piv, stainless hlau tswj nws cov kev ncaj ncees thiab cov tsos txawm tias tom qab lub sij hawm ntev raug rau qhov chaw nyob qhov twg ruaj khov thiab tiv taus corrosion yog qhov tseem ceeb.
Hauv kev xaus, lub corrosion tsis kam ntawm stainless hlau yog qhov muaj kev txaus siab enterplay ntawm cov tshuaj muaj tshuaj lom neeg, microstructure, thiab ib puag ncig. Qhov tsim ntawm cov chromium oxide passive zaj duab xis, thiab cov yam ntxwv tshwj xeeb ntawm cov hlau sib txawv txhua yam los ua kom muaj kev tiv thaiv corrosion. Raws li thev naus laus zis txuas ntxiv mus tshawb fawb ua ntej, txuas ntxiv rau cov kev siv ntawm cov khoom siv uas muaj cov khoom siv no thiab ua kom muaj qhov tseem ceeb tshaj plaws hauv kev tsim khoom thiab kev tsim khoom tshiab thiab engineering.y