Thaum txhuas raug rau saum huab cua nws tam sim ntawd tsim ib txheej nyias, nruj adherent oxide txheej uas khi rau saum npoo thiab txwv kev tawm tsam ntxiv. Hlau cov ntaub ntawv xoob khi hlau oxide uas flakes tawm, nthuav tawm cov hlau tshiab thiab tso cai rau corrosion mus ntxiv.
Ob tus cwj pwm no muaj qhov tshwm sim rau cov qauv, tsheb thiab cov tsev. Lawv kuj txiav txim siab seb cov hlau coj li cas hauv dej, ntsev, acids thiab kev sib cuag nrog lwm yam hlau.
Kev Tiv Thaiv Oxide Txheej ntawm Aluminium
Aluminium oxide cov ntaub ntawv nyob rau hauv vib nas this ntawm raug thiab mus txog ib tug ruaj khov thickness ntawm ob peb nanometers nyob rau hauv huab cua. Cov txheej yog nruam, tus kheej - kho thiab hluav taws xob rwb thaiv tsev, yog li ib qho khawb yog sai sai repassivated es tsis yog qhov chaw corrosion.
Qhov no passivation yog vim li cas aluminium resists atmospheric thiab dej tshiab corrosion thiaj li zoo. Anodizing thickens lub ntuj oxide rau hauv cov khoom siv ruaj khov, tiv thaiv thiab kho kom zoo nkauj, thiab cov chaw anodized tuaj yeem raug kaw ntxiv rau qhov chaw nruj heev.
Rust Formation ntawm Hlau thiab Hlau
Hlau oxide, feem ntau hu ua xeb, nyob hauv lub ntim loj dua li cov hlau uas nws hloov thiab yog ntxeem tau thiab nkig. Nws flakes tawm thiab nthuav tawm cov hlau hauv qab, yog li corrosion nkag mus rau sab hauv kom txog thaum cov seem tau noj.
Xeb nrawm nyob rau hauv lub xub ntiag ntawm noo noo, chlorides thiab oxygen, thiab nws yog ib qho nyuaj rau nres ib zaug. Kev tiv thaiv cia siab rau cov txheej txheej, alloying xws li stainless hlau, lossis cathodic tiv thaiv es tsis yog ntawm cov txheej txheem ntuj tsim.
Galvanic Effects thiab Chloride Attack
Thaum txhuas tiv tauj cov hlau zoo dua nyob rau hauv lub xub ntiag ntawm electrolyte, cov txhuas ua cov anode thiab corrodes nyiam. Cov nyhuv galvanic no yog qhov txaus ntshai tiag tiag hauv kev sib xyaw ua ke- hlau sib dhos thiab tau tswj hwm nrog insulating washers, coatings thiab ceev ceev xaiv fastener.
Chlorides yog nruj rau ob qho tib si hlau tab sis ua txawv. Hlau rusts sai sai nyob rau hauv dej ntsev, thaum txhuas resists nruab nrab chloride daws tau zoo mus txog rau thaum tej yam kev mob ua heev alkaline los yog acidic, qhov twg cov zaj duab xis passive lov.
Tswv yim tiv thaiv thiab xaiv cov khoom
Aluminium tau txais txiaj ntsig los ntawm anodizing, tshuaj hloov pauv txheej, pleev xim thiab xaiv alloy, nrog rau qib marine xws li 5052 thiab 5083 muab cov tshuaj chloride zoo tshaj plaws. Ua kom qhov chaw huv si thiab tsis txhob cuam tshuam cov dej noo txuas ntxiv mus.
Hlau thiab steel cia siab rau galvanizing, pleev xim lossis alloying nrog chromium thiab npib tsib xee. Hauv cov qauv sib xyaw, cov neeg tsim qauv cais cov hlau los yog siv cov khoom hloov pauv kom tawg lub galvanic Circuit Court, uas ua rau ob qho tib si cov ntaub ntawv nyob rau hauv lawv cov kev ua haujlwm nyab xeeb.
Cov lus nug nquag
Q: Vim li cas aluminium tsis xeb zoo li hlau?
Aluminium tsim ib txheej nyias, nruj nreem oxide txheej uas khi rau saum npoo thiab kho nws tus kheej thaum khawb, yog li nws tsis tsim cov khoom flaking corrosion uas siv hlau.
Q: Puas yog aluminium corrode txhua?
Yog lawm. Aluminium tuaj yeem corrode nyob rau hauv ib puag ncig acidic los yog alkaline thiab nyob rau hauv galvanic coupling, tab sis nyob rau hauv nruab nrab atmospheric thiab dej tshiab tej yam kev mob cov passive oxide txheej yuav nres mus rau qhov tsawg kawg nkaus.
Q: Dab tsi yog galvanic corrosion?
Nws tshwm sim thaum ob qhov sib txawv ntawm cov hlau kov nyob rau hauv lub xub ntiag ntawm ib qho electrolyte, ua rau cov hlau tsis tshua muaj zog, feem ntau yog txhuas, kom corrode nyiam ntawm qhov chaw sib cuag.
Q: Yuav tiv thaiv aluminium li cas?
Anodizing, chemical conversion txheej, pleev xim thiab xaiv marine-qib alloys xws li 5052 thiab 5083 txhua yam txhim kho corrosion kuj nyob rau hauv xav tau ib puag ncig.
Q: Dab tsi yog qhov ruaj khov sab nraum zoov, txhuas lossis hlau?
Tsis muaj kev tiv thaiv hlau xeb thiab poob seem, thaum txhuas tsim cov txheej txheem ruaj khov, yog li txhuas feem ntau xav tau kev saib xyuas tsawg dua hauv kev pabcuam sab nraum zoov.