1. Corrosion tsis kam ntawm titanium hauv tshuaj lom neeg
1. Nitric acid
Nitric acid yog oxidizing acid. Titanium tuav cov yeeb yaj kiab oxide tuab ntawm nws qhov chaw hauv nitric acid. Yog li ntawd, titanium muaj zoo heev corrosion kuj nyob rau hauv nitric acid. Tus nqi corrosion ntawm titanium nce nrog qhov nce ntawm qhov kub ntawm cov tshuaj nitric acid. Thaum qhov kub ntawm 190 thiab 240 degree thiab qhov concentration ntawm 20% thiab 70%, nws tus nqi corrosion tuaj yeem ncav cuag 10 mm / a. Txawm li cas los xij, ntxiv me me ntawm silicon-muaj cov tebchaw rau cov tshuaj nitric acid tuaj yeem tiv thaiv corrosion ntawm high-temperature nitric acid ntawm titanium; Piv txwv li, tom qab ntxiv cov roj silicone rau 40% high-temperature nitric acid tov, tus nqi corrosion yuav raug txo kom tsawg. Kuj tseem muaj cov ntaub ntawv hais tias qis dua 500 degree, titanium muaj qib siab ntawm corrosion kuj nyob rau hauv 40% mus rau 80% nitric acid tov thiab chav. Hauv fuming nitric acid, thaum cov ntsiab lus nitrogen dioxide ntau dua 2%, cov dej tsis txaus ua rau muaj zog exothermic, ua rau tawg.
2. Sulfuric acid
Sulfuric acid yog ib qho muaj zog txo cov kua qaub. Titanium muaj qee yam kev tiv thaiv corrosion rau qhov kub thiab txias thiab tsis tshua muaj siab sulfuric acid daws. Ntawm 0 degree, nws tuaj yeem tiv taus corrosion ntawm sulfuric acid nrog rau qhov concentration txog li 20%. Raws li qhov concentration ntawm cov kua qaub thiab qhov kub thiab txias, tus nqi corrosion nce. Yog li ntawd, titanium muaj tsis zoo stability nyob rau hauv sulfuric acid. Txawm nyob rau hauv chav tsev kub nrog yaj oxygen, titanium tsuas yog tiv taus corrosion ntawm 5% sulfuric acid. Ntawm 100 degree, titanium tsuas tuaj yeem tiv thaiv corrosion ntawm 0.2% sulfuric acid. chlorine muaj cov nyhuv inhibitory ntawm corrosion ntawm titanium hauv sulfuric acid, tab sis ntawm 90 degree thiab sulfuric acid concentration ntawm 50%, chlorine accelerates corrosion ntawm titanium thiab txawm ua rau hluav taws. Kev tiv thaiv corrosion ntawm titanium hauv sulfuric acid tuaj yeem txhim kho los ntawm kev qhia huab cua, nitrogen lossis ntxiv oxidants thiab high-valent hnyav hlau ions rau hauv cov tshuaj. Yog li ntawd, titanium tsis tshua muaj nqi nyob rau hauv sulfuric acid.
3. Alkali daws
Titanium muaj qhov zoo corrosion kuj nyob rau hauv feem ntau alkaline daws. Tus nqi corrosion nce nrog cov concentration thiab kub ntawm cov tshuaj. Thaum cov pa oxygen, ammonia lossis carbon dioxide muaj nyob rau hauv cov tshuaj alkali, qhov corrosion ntawm titanium yuav nrawm dua. Hauv cov tshuaj alkali uas muaj hydrogen oxide, qhov corrosion kuj ntawm titanium tsis zoo heev. Txawm li cas los xij, cov tshuaj tiv thaiv corrosion hauv sodium hydroxide yog qhov zoo dua li hauv potassium hydroxide, thiab nws muaj zog corrosion kuj txawm nyob rau hauv high-kub thiab high-concentration sodium hydroxide tov. Piv txwv li, tus nqi corrosion ntawm titanium hauv 73% sodium hydroxide tov ntawm 130 degree tsuas yog 0.18mm / a. Titanium yog txawv los ntawm lwm yam hlau nyob rau hauv hais tias nws yuav tsis tsim kev nyuaj siab corrosion cracking nyob rau hauv sodium hydroxide tov, tab sis ntev ntev yuav ua tau hydrogen embrittlement. Yog li ntawd, kev siv kub ntawm titanium hauv caustic soda thiab lwm yam alkaline daws yuav tsum tsawg dua los yog sib npaug rau 93.33 degree.
4. Cov tshuaj chlorine
Kev ruaj ntseg ntawm titanium hauv chlorine nyob ntawm cov dej hauv cov tshuaj chlorine. Txawm li cas los xij, nws tsis yog corrosion-resistant nyob rau hauv qhuav chlorine thiab muaj kev pheej hmoo ua rau combustion. Yog li ntawd, titanium cov ntaub ntawv yuav tsum muaj cov ntsiab lus dej thaum siv chlorine. Cov ntsiab lus dej yuav tsum tau ua kom titanium passivated hauv cov tshuaj chlorine muaj feem xyuam rau yam xws li lub siab, ntws tus nqi, thiab kub ntawm chlorine.
5. Organic media
Titanium muaj corrosion kuj siab nyob rau hauv roj av, toluene, phenol, formaldehyde, trichloroethane, acetic acid, citric acid, monochloroacetic acid, thiab lwm yam. Thaum boiling point thiab tsis inflation, titanium yuav hnyav corroded nyob rau hauv formic acid hauv qab no 25%. Nyob rau hauv cov kev daws teeb meem uas muaj acetic anhydride, titanium yuav tsis tsuas yog hnyav corroded tag nrho tab sis kuj tsim pitting corrosion. Rau ntau cov organic xov xwm ntsib nyob rau hauv cov organic synthesis txheej txheem, xws li nyob rau hauv zus tau tej cov propylene oxide, phenol, acetone, chloroacetic acid thiab lwm yam chemical media, titanium muaj zoo corrosion kuj dua stainless hlau thiab lwm yam ntaub ntawv.
2. Ob peb lub zos corrosion yam ntxwv ntawm titanium
6. Crevice corrosion Titanium muaj zog tshwj xeeb rau crevice corrosion, thiab crevice corrosion tsuas yog tshwm sim nyob rau hauv ob peb chemical media. Crevice corrosion ntawm titanium yog ze ze rau qhov kub thiab txias, chloride concentration, pH tus nqi thiab qhov loj ntawm qhov crevice. Raws li cov ntaub ntawv tseem ceeb, crevice corrosion yog nquag tshwm sim thaum qhov kub ntawm cov chlorine ntub dej siab tshaj 85 degree. Piv txwv li, qee lub chaw tsim khoom siv ntau lub tsev ntim khoom kom ncaj qha cov roj chlorine ntub dej mus rau 65-70 degree ua ntej nkag mus rau titanium cooler los txhim kho cov kev tiv thaiv rau crevice corrosion, thiab cov nyhuv tseem ceeb heev. Kev xyaum tau ua pov thawj tias qhov ntsuas kub qis yog ib txoj hauv kev zoo los tiv thaiv crevice corrosion. Titanium crevice corrosion kuj tau tshwm sim nyob rau hauv high-temperature sodium chloride tov. Nyob rau hauv luv luv, rau cov khoom thiab cov khoom ua rau crevice corrosion, xws li sealing nto, expansion pob qij txha ntawm cov nplooj ntawv thiab cov hlab, phaj kub exchangers, kev sib cuag ntawm ntauwd daim hlau thiab ntauwd lub cev, thiab fasteners nyob rau hauv yees, titanium alloys xws li Ti{{ 4}}.2 Pd yuav tsum tau siv. Qhov khoob thiab qhov chaw nyob ruaj khov yuav tsum zam thaum tsim. Piv txwv li, fasteners nyob rau hauv yees yuav tsum tau txuas nrog tsawg li sai tau nrog bolts. Lub expansion sib koom ua ke thiab sealing vuam qauv ntawm cov nplooj ntawv thiab cov hlab yog zoo dua li yooj yim expansion pob qij txha. Rau flange sealing nto, asbestos pads yuav tsum tsis txhob siv, thiab polytetrafluoroethylene zaj duab xis-pob asbestos pads yuav tsum tau siv.
7. High-kub corrosion
Qhov kub-kub corrosion kuj ntawm titanium nyob ntawm tus yam ntxwv ntawm qhov nruab nrab thiab kev ua haujlwm ntawm nws tus kheej nto oxide zaj duab xis. Titanium tuaj yeem siv los ua cov khoom siv mus txog 426 degree hauv huab cua lossis oxidizing cua, tab sis nyob ib ncig ntawm 250 degree, titanium pib nqus hydrogen heev. Nyob rau hauv ib qho chaw hydrogen tag nrho, thaum qhov kub nce mus txog 316 degree, titanium absorbs hydrogen thiab ua nkig. Yog li ntawd, tsis muaj kev sim dav, titanium yuav tsum tsis txhob siv rau hauv cov khoom siv tshuaj nrog qhov kub siab tshaj 330 degree. Xav txog hydrogen absorption thiab mechanical zog, kev khiav hauj lwm kub ntawm tag nrho cov-titanium siab hlab ntsha yuav tsum tsis txhob ntau tshaj 250 degree, thiab lub sab sauv txwv ntawm kev khiav hauj lwm kub ntawm titanium raj rau tshav kub exchangers yog hais txog 316 degree.
8. Kev ntxhov siab corrosion
Tsuas yog ob peb tus neeg tshaj tawm, kev lag luam ntshiab titanium muaj kev tiv thaiv zoo rau kev ntxhov siab corrosion, thiab qhov tshwm sim ntawm kev puas tsuaj rau cov khoom siv titanium vim kev ntxhov siab corrosion tseem tsis tshua muaj. Kev lag luam passive titanium tsuas yog ua rau muaj kev ntxhov siab hauv xov xwm xws li fuming nitric acid, qee cov tshuaj methanol lossis qee cov tshuaj hydrochloric acid, high-temperature hypochlorites, molten ntsev ntawm qhov kub ntawm 300-450 degree lossis NaCl-muaj cua, carbon disulfide, n-hexane thiab qhuav chlorine. Txoj kev nyiam ntawm titanium rau kev ntxhov siab corrosion tawg hauv nitric acid maj mam nce nrog qhov nce ntawm NO2 cov ntsiab lus thiab txo cov ntsiab lus dej. Qhov kev ntxhov siab corrosion ntawm titanium nce mus txog nws qhov siab tshaj plaws hauv anhydrous nitric acid uas muaj 20% dawb NO2. Thaum cov ntsiab lus nitric acid muaj ntau dua 6.{{10}}}% NO2 thiab tsawg dua 0.7% H2O, kev lag luam ntshiab titanium kuj yuav raug kev nyuaj siab corrosion tawg txawm nyob rau hauv chav tsev kub. Kev ntxhov siab hnyav corrosion thiab tawg tau tshwm sim hauv kuv lub tebchaws thaum cov khoom siv titanium tau siv hauv 98% concentrated nitric acid. Muaj cov ntshiab titanium rhiab heev rau kev ntxhov siab corrosion tawg hauv 10% hydrochloric acid tov, thiab titanium tsim kev ntxhov siab corrosion hauv 0.4% hydrochloric acid ntxiv rau cov tshuaj methanol. Hauv cov ntsiab lus, txawm hais tias titanium muaj kev ntxhov siab corrosion puas hauv qee qhov tshwj xeeb tshaj tawm, piv nrog lwm cov hlau, titanium muaj kev tiv thaiv zoo rau kev ntxhov siab corrosion tawg; titanium muaj zog corrosion kuj nyob rau hauv acids thiab alkalis, thiab nws muaj peev xwm tsim ib tug oxide zaj duab xis nyob rau hauv acids thiab alkalis, tab sis nws kuj yog conditional. Kuv vam tias nws yuav pab tau koj thaum siv peb cov ntaub ntawv.
