Peb siv cov ncuav qab zib los txhim kho koj qhov kev paub.Los ntawm kev txuas ntxiv mus saib lub vev xaib no, koj pom zoo rau peb siv cov ncuav qab zib.Cov ntaub ntawv ntxiv.
Lub tshuab hluav taws xob ntshiab los yog ntshiab huv muaj xws li cov tshuab hluav taws xob, tswj cov kav dej, cov kav dej xa dej lossis cov kav dej, cov khoom siv hluav taws xob lossis cov khoom sib npaug ntawm cov ntsuas kub, ntsuas ntsuas, ntsuas qhov ntsuas siab, kev nyab xeeb li qub, thiab cov khoom ntim ntim ntim.
Feem ntau ntawm cov khoom no yog ua los ntawm 316 L stainless hlau thiab muaj fluoropolymer gaskets (feem ntau polytetrafluoroethylene, los yog Teflon los yog PTFE), nrog rau ib nrab hlau los yog lwm yam elastomeric cov ntaub ntawv.
Cov khoom no muaj kev cuam tshuam rau corrosion los yog degradation thaum siv, uas cuam tshuam rau qhov zoo ntawm cov khoom siv huv huv (CS) tiav.Qhov project tau piav qhia hauv tsab xov xwm no tau soj ntsuam cov qauv stainless hlau los ntawm plaub CS system cov ntaub ntawv tshawb fawb, ntsuas qhov kev pheej hmoo ntawm kev cuam tshuam corrosion ntawm cov txheej txheem thiab cov txheej txheem tseem ceeb hauv engineering, thiab kuaj cov khoom thiab cov hlau hauv condensate.
Cov qauv ntawm corroded piping thiab tis system Cheebtsam yog muab tso rau los soj ntsuam corrosion los ntawm cov khoom.9 Rau txhua qhov tshwj xeeb, qhov sib txawv ntawm qhov chaw tau raug soj ntsuam.Piv txwv li, tus qauv blush thiab corrosion kuj raug soj ntsuam.
Qhov chaw ntawm cov qauv siv tau raug soj ntsuam rau qhov pom ntawm qhov muag pom los ntawm kev kuaj pom, Auger electron spectroscopy (AES), electron spectroscopy rau tshuaj ntsuam xyuas (ESCA), scanning electron microscopy (SEM) thiab X-ray photoelectron spectroscopy (XPS).
Cov txheej txheem no tuaj yeem nthuav tawm lub cev thiab atomic zog ntawm corrosion thiab deposits, nrog rau kev txiav txim siab cov ntsiab lus tseem ceeb uas cuam tshuam rau cov khoom ntawm cov kua dej los yog cov khoom kawg.ib
Corrosion khoom ntawm stainless hlau tuaj yeem siv tau ntau hom, xws li txheej carmine ntawm hlau oxide (xim av lossis xim liab) rau saum npoo hauv qab lossis saum txheej hlau oxide (dub lossis grey) 2.Muaj peev xwm tsiv teb tsaws chaw.
Cov hlau oxide txheej (dub blush) yuav thicken nyob rau lub sij hawm raws li cov deposits ua ntau pronounced, raws li pov thawj los ntawm hais los yog deposits pom nyob rau ntawm qhov chaw ntawm lub sterilization chamber thiab cov khoom los yog ntim tom qab chav sterilization, muaj kev tsiv teb tsaws.Kev ntsuam xyuas ntawm cov qauv condensate pom qhov sib txawv ntawm cov sludge thiab cov nyiaj soluble hlau hauv CS kua.plaub
Txawm hais tias muaj ntau qhov laj thawj rau qhov tshwm sim no, CS generator feem ntau yog tus pab txhawb nqa loj.Nws tsis yog qhov tsis yooj yim kom pom cov hlau oxide liab (xim av / xim liab) ntawm qhov chaw thiab hlau oxide (dub / grey) hauv cov vents uas maj mam tsiv los ntawm CS faib system.6
CS kev faib tawm yog ib qho kev teeb tsa nrog ntau lub ntsiab lus siv xaus rau ntawm thaj chaw deb lossis qhov kawg ntawm lub ntsiab lus tseem ceeb thiab ntau ceg subheaders.Lub kaw lus yuav suav nrog ntau tus neeg tswj hwm los pab pib lub siab / qhov kub thiab txias ntawm cov ntsiab lus tshwj xeeb ntawm kev siv uas tej zaum yuav yog cov ntsiab lus corrosion.
Corrosion kuj tuaj yeem tshwm sim hauv cov cuab yeej siv tu cev uas tau muab tso rau ntawm ntau lub ntsiab lus hauv qhov system kom tshem tawm cov condensate thiab huab cua los ntawm cov dej huv huv los ntawm cov ntxiab, cov kav dej hauv qab / tso tawm los yog lub taub hau condensate.
Feem ntau, kev rov qab tsiv teb tsaws yog qhov zoo li qhov uas cov pob zeb xeb ua rau ntawm lub ntxiab thiab loj hlob tuaj rau hauv thiab dhau ntawm cov kav dej uas nyob ib sab los yog cov khoom siv siv;xeb uas tsim hauv cov ntxiab lossis lwm yam khoom tuaj yeem pom nyob rau hauv qhov chaw nrog kev tsiv teb tsaws tsis tu ncua downstream thiab ntws.
Qee cov khoom siv hlau tsis muaj steel kuj muaj ntau yam nruab nrab mus rau qib siab ntawm cov qauv hlau, suav nrog delta ferrite.ferrite crystals ntseeg tau tias yuav txo qis kev tiv thaiv corrosion, txawm tias lawv tuaj yeem nyob hauv tsawg li 1-5%.
Ferrite kuj tsis yog resistant rau corrosion li lub austenitic siv lead ua qauv, yog li nws yuav nyiam corrode.Ferrites tuaj yeem raug kuaj pom tseeb nrog kev sojntsuam ferrite thiab ib nrab raug nrog cov hlau nplaum, tab sis muaj cov kev txwv tseem ceeb.
Los ntawm kev teeb tsa, los ntawm kev pib ua haujlwm, thiab pib ntawm lub tshuab hluav taws xob CS tshiab thiab cov kav xa dej, muaj ntau yam uas ua rau muaj kev xeb:
Sij hawm dhau mus, cov khoom corrosive xws li cov no tuaj yeem tsim cov khoom siv corrosion thaum lawv sib ntsib, sib xyaw ua ke, thiab sib tshooj nrog cov hlau thiab hlau.Cov hmoov av dub feem ntau pom thawj zaug hauv lub tshuab hluav taws xob, tom qab ntawd nws tshwm sim hauv lub tshuab hluav taws xob tso tawm cov kav dej thiab nws thiaj li thoob plaws hauv CS kev faib khoom.
SEM tsom xam tau ua los qhia cov microstructure ntawm corrosion los ntawm cov khoom uas npog tag nrho cov nto nrog cov muaju thiab lwm yam hais.Lub keeb kwm yav dhau los yog hauv qab ntawm qhov chaw uas cov khoom tau pom txawv ntawm ntau qib ntawm cov hlau (Fig. 1-3) mus rau cov qauv, xws li silica / hlau, xuab zeb, vitreous, homogeneous deposits (Fig. 4).Cov chav ntxiab hauv qab kuj tau txheeb xyuas (Daim duab 5-6).
AES xeem yog ib txoj kev tshuaj ntsuam uas siv los txiav txim qhov saum npoo ntawm stainless hlau thiab kuaj xyuas nws cov corrosion kuj.Nws kuj qhia tau hais tias qhov deterioration ntawm cov zaj duab xis passive thiab qhov txo qis hauv cov ntsiab lus ntawm chromium nyob rau hauv cov zaj duab xis passive raws li qhov deteriorates vim corrosion.
Txhawm rau ua kom pom qhov muaj pes tsawg leeg ntawm qhov chaw ntawm txhua tus qauv, AES scans (concentration profiles ntawm cov ntsiab lus saum npoo tob) tau siv.
Txhua qhov chaw siv rau SEM tsom xam thiab augmentation tau ua tib zoo xaiv los muab cov ntaub ntawv los ntawm cov cheeb tsam ib txwm.Txhua qhov kev tshawb fawb tau muab cov ntaub ntawv los ntawm ob peb txheej molecular saum toj kawg nkaus (kwv yees ntawm 10 angstroms [Å] ib txheej) mus rau qhov tob ntawm cov hlau alloy (200-1000 Å).
Qhov tseem ceeb ntawm cov hlau (Fe), chromium (Cr), npib tsib xee (Ni), oxygen (O) thiab carbon (C) tau raug kaw hauv txhua cheeb tsam ntawm Rouge.AES cov ntaub ntawv thiab cov txiaj ntsig tau piav qhia hauv cov ntaub ntawv kawm.
Tag nrho cov txiaj ntsig ntawm AES rau thawj cov xwm txheej qhia tau hais tias muaj zog oxidation tshwm sim ntawm cov qauv uas muaj qhov txawv txav ntawm Fe thiab O (hlau oxides) thiab qis Cr cov ntsiab lus ntawm qhov chaw.Qhov kev tso nyiaj ruddy no ua rau muaj kev tso tawm cov khoom uas tuaj yeem ua rau cov khoom thiab qhov chaw sib cuag nrog cov khoom.
Tom qab lub ntsej muag raug tshem tawm, cov qauv "passivated" tau pom qhov ua tiav ntawm cov yeeb yaj kiab passive, nrog Cr mus txog qib siab dua li Fe, nrog Cr: Fe nto piv ntawm 1.0 txog 2.0 thiab tag nrho tsis muaj hlau oxide.
Ntau qhov chaw ntxhib raug tshuaj xyuas siv XPS / ESCA los sib piv cov ntsiab lus tseem ceeb thiab spectral oxidation xeev ntawm Fe, Cr, sulfur (S), calcium (Ca), sodium (Na), phosphorus (P), nitrogen (N), thiab O. thiab C (table A).
Nws muaj qhov sib txawv ntawm Cr cov ntsiab lus los ntawm qhov tseem ceeb ze rau cov txheej txheem passivation mus rau cov nqi qis feem ntau pom nyob rau hauv lub hauv paus alloys.Cov qib ntawm cov hlau thiab chromium pom nyob rau saum npoo yog txawv thicknesses thiab qib ntawm rouge deposits.Kev ntsuam xyuas XPS tau pom tias muaj kev nce ntxiv hauv Na, C lossis Ca ntawm qhov chaw ntxhib piv rau qhov chaw huv thiab tsis huv.
Kev kuaj XPS kuj tau pom cov qib siab C hauv cov hlau liab (dub) liab thiab Fe(x)O(y) (hlau oxide) liab.XPS cov ntaub ntawv tsis muaj txiaj ntsig rau kev nkag siab qhov hloov pauv ntawm qhov chaw thaum lub sij hawm xeb vim nws ntsuas ob qho tib si liab thiab cov hlau hauv paus.Kev kuaj XPS ntxiv nrog cov qauv loj dua yuav tsum tau ntsuas kom zoo.
Cov kws sau ntawv yav dhau los kuj muaj teeb meem ntsuas XPS cov ntaub ntawv.10 Kev soj ntsuam teb thaum lub sijhawm tshem tawm tau pom tias cov ntsiab lus carbon siab thiab feem ntau raug tshem tawm los ntawm kev pom thaum ua haujlwm.SEM micrographs coj los ua ntej thiab tom qab kev kho qhov txhab tshem tawm qhia txog qhov kev puas tsuaj saum npoo los ntawm cov deposits, nrog rau pitting thiab porosity, uas ncaj qha cuam tshuam rau corrosion.
XPS cov txiaj ntsig tom qab passivation tau pom tias Cr: Fe cov ntsiab lus piv rau ntawm qhov chaw tau ntau dua thaum cov yeeb yaj kiab passivation tau rov tsim dua, yog li txo tus nqi ntawm corrosion thiab lwm yam tsis zoo ntawm qhov chaw.
Cov qauv daim coupon tau pom qhov nce ntxiv ntawm Cr: Fe piv ntawm "raws li yog" nto thiab qhov chaw passivated.Thawj Cr: Fe ratios tau sim nyob rau hauv thaj tsam ntawm 0.6 txog 1.0, thaum tom qab kev kho mob passivation ratios ntawm 1.0 mus rau 2.5.Qhov tseem ceeb rau electropolished thiab passivated stainless hlau yog nyob nruab nrab ntawm 1.5 thiab 2.5.
Hauv cov qauv uas tau ua tom qab ua tiav, qhov siab tshaj plaws ntawm qhov sib piv Cr: Fe (tsim siv AES) nyob ntawm 3 txog 16 Å.Lawv sib piv nrog cov ntaub ntawv los ntawm cov kev tshawb fawb yav dhau los luam tawm los ntawm Coleman2 thiab Roll.9 Qhov chaw ntawm tag nrho cov qauv muaj cov qauv ntawm Fe, Ni, O, Cr, thiab C. Cov qib qis ntawm P, Cl, S, N, Ca, thiab Na kuj tau pom nyob rau hauv feem ntau ntawm cov qauv.
Cov residues no yog cov tshuaj ntxuav tes, dej huv, lossis electropolishing.Raws li kev soj ntsuam ntxiv, qee qhov kev sib kis ntawm silicon tau pom nyob rau saum npoo thiab ntawm ntau theem ntawm austenite siv lead ua nws tus kheej.Lub hauv paus zoo li yog cov ntsiab lus silica ntawm cov dej / chav dej, cov tshuab polishes, lossis yaj lossis etched pom iav hauv CS tiam cell.
Corrosion khoom pom nyob rau hauv CS systems tau tshaj tawm tias nws txawv heev.Qhov no yog vim muaj kev sib txawv ntawm cov tshuab no thiab qhov chaw ntawm ntau yam khoom xws li li qub, ntxiab thiab lwm yam khoom siv uas tuaj yeem ua rau cov khoom siv corrosive thiab corrosion.
Tsis tas li ntawd, cov khoom siv hloov pauv feem ntau tau nkag mus rau hauv qhov system uas tsis zoo passivated.Cov khoom siv corrosion kuj tseem cuam tshuam los ntawm kev tsim ntawm CS generator thiab cov dej zoo.Qee hom generator teeb yog reboilers thaum lwm tus yog tubular flashers.CS generators feem ntau siv cov ntxaij vab tshaus kawg kom tshem tawm cov dej noo ntawm chav huv, thaum lwm lub tshuab hluav taws xob siv baffles lossis cyclones.
Qee qhov tsim cov hlau yuav luag patina hauv cov yeeb nkab xa khoom thiab cov hlau liab npog nws.Lub baffled block tsim cov yeeb yaj kiab hlau dub nrog cov hlau oxide blush hauv qab thiab tsim qhov tshwm sim thib ob saum toj kawg nkaus hauv daim ntawv ntawm lub ntsej muag sooty uas yooj yim dua los so ntawm qhov chaw.
Raws li txoj cai, qhov no ferruginous-soot-zoo li tso nyiaj ntau tshaj li cov hlau-liab, thiab yog ntau lub xov tooj ntawm tes.Vim tias muaj zog oxidation ntawm cov hlau nyob rau hauv lub condensate, cov sludge generated nyob rau hauv lub condensate channel nyob rau hauv qab ntawm cov yeeb nkab tis muaj hlau oxide sludge nyob rau sab saum toj ntawm cov hlau sludge.
Cov hlau oxide blush hla dhau los ntawm condensate collector, pom nyob rau hauv lub ntws, thiab cov txheej saum toj kawg nkaus yog yooj yim rubbed tawm ntawm qhov chaw.Cov dej zoo ua lub luag haujlwm tseem ceeb hauv cov tshuaj muaj pes tsawg leeg ntawm blush.
Cov ntsiab lus hydrocarbon siab dua ua rau cov kua nplaum ntau dhau hauv daim di ncauj, thaum cov ntsiab lus silica ntau dua ua rau cov ntsiab lus silica ntau dua, uas ua rau lub ntsej muag du lossis glossy.Raws li tau hais ua ntej, cov iav tsom iav pom dej kuj muaj qhov ua rau corrosion, cia cov khib nyiab thiab silica nkag mus rau hauv lub cev.
Cov phom yog qhov ua rau muaj kev txhawj xeeb hauv cov tshuab ua pa vim cov txheej tuab tuaj yeem tsim cov khoom siv.Cov khoom no muaj nyob rau ntawm chav dej los yog hauv chav ua kom tsis muaj menyuam.Cov tshooj hauv qab no piav qhia txog cov teebmeem tshuaj uas tshwm sim tau.
Lub As-Yog SEMs hauv daim duab 7 thiab 8 qhia txog microcrystalline xwm ntawm chav kawm 2 carmine nyob rau hauv rooj plaub 1. Ib qho tshwj xeeb ntom matrix ntawm hlau oxide crystals tsim rau ntawm qhov chaw nyob rau hauv daim ntawv ntawm ib tug nplua-grained residue.Decontaminated thiab passivated nto tau pom kev puas tsuaj uas ua rau muaj qhov ntxhib thiab ntxhib me ntsis ntxhib ntxhib ntxhib los mos raws li pom hauv daim duab 9 thiab 10.
NPP scan hauv fig.11 qhia tau hais tias thawj lub xeev ntawm qhov qub nto nrog hnyav hlau oxide rau nws. Lub passivated thiab derouged nto (Daim duab 12) qhia tias zaj duab xis passive tam sim no muaj qhov siab Cr (liab kab) cov ntsiab lus saum Fe (dub kab) ntawm> 1.0 Cr: Fe piv. Lub passivated thiab derouged nto (Daim duab 12) qhia tias zaj duab xis passive tam sim no muaj qhov siab Cr (liab kab) cov ntsiab lus saum Fe (dub kab) ntawm> 1.0 Cr: Fe piv. Пассивированная и обесточенная поверхность (рис. 12) указывает на то, что пассивная пленка топеперь имет асная линия) по сравнению с Fe (черная линия) при соотношении Cr:Fe > 1,0. Lub passivated thiab de-energized nto (Daim duab 12) qhia tias zaj duab xis passive tam sim no muaj cov ntsiab lus ntawm Cr (kab liab) piv rau Fe (kab dub) ntawm qhov piv ntawm Cr: Fe > 1.0.钝化和去皱表面（图12）表明，钝化膜现在的Cr（红线）含量高于Fe（黑线），Cr:Fe 比率> 1.0. Cr (红线)含量高于Fe（黑线），Cr:Fe 比率> 1.0. Пассивированная и морщинистая поверхность (рис. 12) показывает, что пассивированная пленка теоперь божет имет Cr (красная линия), чем Fe (черная линия), при соотношении Cr:Fe > 1,0. Lub passivated thiab wrinkled nto (Fig. 12) qhia tau hais tias cov passivated zaj duab xis tam sim no muaj ib tug siab dua Cr ntsiab lus (liab kab) tshaj Fe (dub kab) ntawm ib tug Cr: Fe piv> 1.0.
Ib lub thinner (< 80 Å) passivating chromium oxide zaj duab xis muaj kev tiv thaiv ntau dua li ntau pua angstrom tuab crystalline hlau oxide zaj duab xis los ntawm lub hauv paus hlau thiab nplai txheej nrog cov ntsiab lus hlau ntau dua 65%.
Cov tshuaj muaj pes tsawg leeg ntawm passivated thiab wrinkled nto yog tam sim no piv rau passivated polished cov ntaub ntawv.Lub sediment nyob rau hauv rooj plaub 1 yog ib chav kawm 2 sediment muaj peev xwm tsim nyob rau hauv situ;raws li nws accumulates, loj hais yog tsim uas migrate nrog lub chav.
Nyob rau hauv cov ntaub ntawv no, lub corrosion qhia yuav tsis ua rau loj flaws los yog deterioration ntawm nto zoo.Ib txwm wrinkling yuav txo cov nyhuv corrosive ntawm qhov chaw thiab tshem tawm qhov muaj peev xwm ntawm kev tsiv teb tsaws zoo ntawm cov khoom uas tuaj yeem pom.
Hauv daim duab 11, AES cov txiaj ntsig tau pom tias cov txheej tuab nyob ze ntawm qhov chaw muaj qib siab dua ntawm Fe thiab O (500 Å ntawm hlau oxide; txiv qaub ntsuab thiab xiav kab, ntsig txog), hloov mus rau doped qib ntawm Fe, Ni, Cr, thiab O. Fe concentration (xiav kab) ntau dua li ntawm lwm yam hlau, nce los ntawm 35% ntawm cov hlau nyob rau saum npoo.
Nyob rau saum npoo, O theem (lub teeb ntsuab kab) mus los ntawm yuav luag 50% nyob rau hauv lub alloy mus yuav luag xoom ntawm ib tug oxide zaj duab xis thickness ntawm ntau tshaj 700 Å. Ni (kab ntsuab tsaus) thiab Cr (liab kab) qib qis heev ntawm qhov chaw (< 4%) thiab nce mus rau qib qub (11% thiab 17%, feem) ntawm qhov tob ntawm alloy. Ni (kab ntsuab tsaus) thiab Cr (liab kab) qib qis heev ntawm qhov chaw (< 4%) thiab nce mus rau qib qub (11% thiab 17%, feem) ntawm qhov tob ntawm alloy. Уровни Ni (темно-зеленая линия) и Cr (красная линия) чрезвычайно низки на поверхности (<4%) и увеличиваютроя доно (1% 17% соответственно) hauv глубине сплава. Qib Ni (kab ntsuab tsaus) thiab Cr (kab liab) yog qhov tsawg kawg nkaus ntawm qhov chaw (<4%) thiab nce mus rau qib qub (11% thiab 17% raws li) sib sib zog nqus hauv cov hlau.表面的Ni（深绿线）和Cr（红线）水平极低（<4%），而在合金深度处增加到正常水平（7% 1分）。表面的Ni（深绿线）和Cr（红线）水平极低（<4%），而在合金深度处增加到歌常水别（和分别到歌常水别1 Уровни Ni (темно-зеленая линия) и Cr (красная линия) на поверхности чрезвычайно низки (<4%) и увеличиваютрьроя донм ине сплава (11% thiab 17% соответственно). Cov theem ntawm Ni (kab ntsuab tsaus) thiab Cr (liab kab) ntawm qhov chaw yog qhov tsawg heev (<4%) thiab nce mus rau qib ib txwm sib sib zog nqus hauv cov hlau (11% thiab 17% feem).
AES duab in fig.12 qhia tau hais tias rouge (hlau oxide) txheej tau raug tshem tawm thiab cov yeeb yaj kiab passivation tau rov qab los.Nyob rau hauv 15 Å thawj txheej, Cr theem (kab liab) yog siab tshaj Fe theem (kab dub), uas yog ib tug passive zaj duab xis.Thaum pib, Ni cov ntsiab lus ntawm qhov chaw yog 9%, nce 60-70 Å saum toj no Cr qib (± 16%), thiab tom qab ntawd nce mus rau qib alloy ntawm 200 Å.
Pib ntawm 2%, qib carbon (xiav kab) poob rau xoom ntawm 30 Å. Fe theem pib qis (< 15%) thiab tom qab ntawd sib npaug rau qib Cr ntawm 15 Å thiab txuas ntxiv mus rau qib alloy ntawm ntau tshaj 65% ntawm 150 Å. Fe theem pib qis (< 15%) thiab tom qab ntawd sib npaug rau qib Cr ntawm 15 Å thiab txuas ntxiv mus rau qib alloy ntawm ntau tshaj 65% ntawm 150 Å. Уровень Fe вначале низкий (< 15%), позже равен уровню Cr при 15 Å и продолжает увеличиваться до в ураловня до 6 ураловня Å. Fe theem pib qis (< 15%), tom qab sib npaug ntawm Cr qib ntawm 15 Å thiab txuas ntxiv mus rau ntau dua 65% alloy qib ntawm 150 Å. Fe 含量最初很低(< 15%)，后来在15 Å 时等于Cr 含量，并在150 Å 时继续增加到超的向 65% Fe 含量最初很低(< 15%)，后来在15 Å 时等于Cr 含量，并在150 Å 时继续增加到超的向 65% Содержание Fe изначально низкое (< 15 %), позже оно равняется содержанию Cr при 15 Å и продолжает я увапри 65% ntawm 150 Å. Cov ntsiab lus Fe yog thawj zaug qis (< 15%), tom qab ntawd nws sib npaug ntawm Cr cov ntsiab lus ntawm 15 Å thiab txuas ntxiv mus kom txog thaum cov ntsiab lus alloy siab tshaj 65% ntawm 150 Å.Cr qib nce mus rau 25% ntawm qhov chaw ntawm 30 Å thiab txo mus rau 17% hauv cov hlau.
Qhov siab O theem ze ntawm qhov chaw (lub teeb ntsuab kab) txo qis rau xoom tom qab qhov tob ntawm 120 Å.Qhov kev tshuaj ntsuam no pom tau hais tias ib qho zoo tsim nto passivation zaj duab xis.Cov duab SEM nyob rau hauv daim duab 13 thiab 14 qhia qhov ntxhib, ntxhib thiab ntxeem tau crystalline xwm ntawm qhov chaw 1st thiab 2nd hlau oxide txheej.Lub ntsej muag wrinkled qhia tau hais tias cov nyhuv ntawm corrosion ntawm ib feem pitted ntxhib nto (Figures 18-19).
Cov chaw passivated thiab wrinkled nyob rau hauv daim duab 13 thiab 14 tsis tiv taus oxidation hnyav.Daim duab 15 thiab 16 qhia ib zaj duab xis rov qab los ntawm cov hlau.