Ua thiab tsim ntawm corrosion ntawm titanium rods
Peb feem ntau xav tias titanium thiab titanium alloy cov khoom yuav tsis corrode yooj yim, tab sistitanium alloy rodsfeem ntau corrode. Yuav ua li cas ntawm no? Hauv qab no kuv yuav qhia luv luv txog cov laj thawj thiab cov hom tseem ceeb ntawm kev rov qab corrosion ntawm titanium rods. Txhua tus tuaj yeem zam kev xeb ntawm titanium pas nrig thaum siv.
1. Crevice corrosion: Crevice corrosion yog cov yam ntxwv hauv zos uas tshwm sim hauv cov crevices nruj. Cov kab nrib pleb thiab qhov khoob tuaj yeem tshwm sim los ntawm cov txheej txheem ntawm qhov chaw (xws li flange pob qij txha lossis qhov chaw gasket, kev sib txuas ntawm cov kav dej thiab cov ntawv, bolts lossis rivets, thiab lwm yam), los yog lawv tuaj yeem tshwm sim los ntawm sediment encrustation lossis txheej. Thaum ntxov, nws feem ntau ntseeg tias titanium yuav tsis raug kev txom nyem los ntawm crevice corrosion nyob rau hauv dej hiav txwv thiab ntsev tsuag lawm. Tom qab ntawd, nws yog siv los txwv oxidant noj nyob rau hauv high-temperature chloride media (xws li seawater heat exchangers) thiab chlorine ntub dej (xws li ntub chlorine raj condensers), hydrochloric acid corrosion li, formic acid corrosion, oxalic acid corrosion thiab lwm yam xov xwm. . Media thiab crevice corrosion hardware txaus ntshai thiab kev puas tsuaj tseem tshwm sim.
Crevice corrosion ntawm titanium rods muaj feem xyuam rau ntau yam sib txawv xws li kub, chloride hom thiab immobility, pH, thiab pore loj thiab xam. Tsis tas li ntawd, qhov ua los ntawm titanium thiab cov ntaub ntawv tsis yog xim hlau xws li PTFE, titanium thiab asbestos yog qhov cuam tshuam rau crevice corrosion tshaj qhov ua los ntawm titanium thiab titanium.
2. Pitting corrosion: Pitting corrosion yog ib hom tshiab ntawm kev noj cov hlau passivated. Titanium tsis kam rau pitting corrosion feem ntau zoo heev piv rau hardened steel los yog txhuas tebchaw. Raws li kev siv tus nqi ntawm titanium nyob rau hauv high-temperature concentrated chloride li txuas ntxiv mus, cov nyiaj titanium hlau siv nyob rau hauv pits txuas ntxiv.
Lub titanium anode hopper nyob rau hauv cov nroj tsuag electrolytic zinc, rhuab titanium kauj nyob rau hauv zinc chloride cog, thiab titanium pob valve nyob rau hauv 175 degree 72% calcium chloride nroj tsuag tag nrho raug kev puas tsuaj pitting. Feem ntau, kev noj cov titanium yog teeb meem ntau dua li pitting corrosion, uas feem ntau tshwm sim los ntawm pitting noj ntawm qhov tawg.
3. Kev siv hluav taws xob: Kev siv hluav taws xob yog tus yam ntxwv ntawm kev sib cuag ntawm cov hlau (xws li hluav taws xob tiv tauj) hauv cov txheej txheem electrolyte. Vim tias qhov sib txawv ntawm cov hlau zoo li qhov sib xws, ib qho hlau tuaj yeem ua kom lub depletion (piv txwv li, anodic decomposition) ntawm lwm qhov. oxide zaj duab xis ntawm titanium yog ruaj khov heev thiab feem ntau yog nyob rau hauv lub xeev cathodic. Kev siv hluav taws xob tsis ua kom lub anodic decomposition ntawm titanium.
Nws yog ib qho tsim nyog sau cia tias titanium khaws cov hydrogen hauv lub xeev cathodic thiab thaum kawg ua rau hydrogen embrittlement, yog li nws yog ib qho tseem ceeb los tiv thaiv kev sib txuas ntawm cov hlau sib txuas (xws li txhuas, tooj liab, zinc, thiab lwm yam). Cov qib ntawm cov khoom siv hlau galvanic yog nyob ntawm qhov sib txawv ntawm kev txuas ntxiv ntawm kev sib txuas ntawm cov khoom siv hlau galvanic hauv nruab nrab.
