1.Dab tsi yog qhov zoo thiab cov kev txwv ntawm cov yam tsis kho saum npoo?
Qhov zoo: Tus nqi qis tshaj plaws, tsis muaj kev cuam tshuam cov txheej txheem ntxiv (piv txwv li, tom qab siab -kub ua haujlwm);
Cov kev txwv: cov zinc txheej yog ncaj qha raug, raug rau ya raws thiab ntsev corrosion, thiab tej zaum yuav tsim dawb xeb nyob rau hauv lub sij hawm luv luv (1-3 lub hlis).
2.Dab tsi yog cov qauv kev tiv thaiv tseem ceeb, qhov zoo thiab qhov tsis zoo ntawm chromic acid passivation?
Lub hauv paus ntsiab lus kev tiv thaiv: Chromic acid reacts nrog zinc txheej, tsim ib tug tuab oxide zaj duab xis (20-50nm tuab) feem ntau yog tsim los ntawm Cr³⁺, uas cais cov zinc txheej ntawm dej thiab oxygen.
Qhov zoo: Cov zaj duab xis passivation muaj zog adhesion thiab abrasion tsis kam, txhim kho zinc txheej nruab nrab ntsev tsuag tsis kam los ntawm 2-3 zaug (feem ntau tsis pom cov xeb dawb rau 48-72 teev).
Kev txwv: Ib txwm siv hexavalent chromium passivation ua rau muaj kev pheej hmoo ntawm ib puag ncig (trivalent chromium passivation tam sim no ntau dua, nrog kev txo qis me ntsis tab sis tseem ua raws).
3.Dab tsi yog cov ntsiab cai tiv thaiv, qhov zoo thiab qhov tsis zoo ntawm phosphoric acid passivation?
Lub hauv paus ntsiab lus tiv thaiv: Phosphoric acid reacts nrog zinc txheej los tsim ib txheej crystalline zinc phosphate (50-100nm tuab). Qhov no ntxeem tau zaj duab xis muaj zoo adhesion rau cov xim tom ntej.
Qhov zoo: Nws yog ib puag ncig zoo dua li chromic acid passivation thiab tiv thaiv cov xim detachment thaum lub sij hawm tom qab tha xim.
Cov kev txwv: Ntshiab phosphoric acid passivation nthuav tawm me ntsis qaug zog ntsev tshuaj tiv thaiv (feem ntau tsis pom cov xeb dawb tom qab 36-60 teev), thiab muaj kev tiv thaiv corrosion tsawg thaum siv ib leeg.
4.Dab tsi yog qhov tseem ceeb ntxiv uas cuam tshuam rau kev tiv thaiv corrosion?
Zinc txheej thickness: Lub hauv paus ntawm kev kho saum npoo yog los tiv thaiv zinc txheej. Yog hais tias cov zinc txheej nws tus kheej yog nyias (xws li, 60g / m2 ntawm ob sab), txawm tias passivation thiab oiling, lub neej kev tiv thaiv corrosion yuav luv dua li cov zinc txheej tuab (piv txwv li, 120g / m2 ntawm ob sab). Zinc txheej thickness sawv cev rau "kev tiv thaiv corrosion tseem ceeb," thaum kho saum npoo muab "tus nqi- ntxiv kev tiv thaiv."
Siv ib puag ncig:
Humid/high-nquag ib puag ncig (piv txwv li, thaj chaw ntug dej hiav txwv, hauv qab daus): "Passivation + oiling" lossis siab dua - theem kev kho mob (xws li, xim txheej) yog qhov tseem ceeb. Txwv tsis pub, cov pob dub thiab zinc txheej txheej yuav tshwm sim.
Qhuav hauv tsev ib puag ncig (xws li, cov khoom siv hauv tsev): Passivation ib leeg txaus; tsis tas yuav ntxiv roj ntxiv.
Kev Kho Cov Txheej Txheem Kev Ruaj Ntseg: Yog tias cov zaj duab xis passivation tsis sib npaug (xws li cov txheej txheem uas ploj lawm, tsis txaus zaj duab xis thickness) los yog cov roj zaj duab xis evaporates yooj yim, qhov kev tiv thaiv corrosion tiag tiag yuav txo qis, txawm tias sau tias "C + O." Cov khoom lag luam los ntawm cov tuam txhab ua raws (xws li ISO 14001 tau ntawv pov thawj thiab nrog cov ntaub ntawv soj ntsuam zoo) yuav tsum raug xaiv.
5.Cov lus pom zoo xaiv yog dab tsi?
Rau qhov kawg corrosion tiv thaiv thiab ntev - lub sij hawm cia: Chromic acid passivation + oiling (C + O) yog nyiam (ua tib zoo saib xyuas ib puag ncig, nrog trivalent chromium nyiam).
Yog tias yuav tsum muaj txheej txheej thib ob, xaiv phosphoric acid passivation (P) lossis phosphoric acid passivation + oiling (P + O) kom sib npaug tiv thaiv corrosion thiab xim adhesion.
Yog hais tias tom ntej no siab -kub ua (xws li vuam) yog yuav tsum tau, xaiv untreated (U) los yog ib tug passivation (C / P) kom tsis txhob impurities tsim los ntawm cov roj / passivation zaj duab xis decomposition ntawm kub kub.
Rau cov ntug dej hiav txwv / siab-cov av noo ib puag ncig: Txawm li cas los xij ntawm txoj kev kho mob, xyuas kom cov zinc txheej tuab yog ntau dua lossis sib npaug li 80g / m2 ntawm ob sab, thiab kev kho saum npoo yuav tsum tsis muaj qhov tsis xws luag xws li cov txheej uas ploj lawm thiab cov pinholes.