Feem ntau tshwm sim ntawm siab hlab ntsha corrosion

1.Comprehensive corrosion (tseem hu ua uniform corrosion), uas yog ib qho tshwm sim los ntawm cov tshuaj corrosion los yog electrochemical corrosion, qhov nruab nrab corrosive tuaj yeem ncav cuag txhua qhov ntawm cov hlau nto sib npaug, kom cov hlau muaj pes tsawg leeg thiab lub koom haum yog cov xwm txheej zoo sib xws, tag nrho cov hlau nto yog corroded ntawm tus nqi zoo sib xws. Rau stainless hlau siab hlab ntsha, nyob rau hauv ib tug corrosive ib puag ncig uas tsis muaj PH nqi, lub passivation zaj duab xis yuav poob nws cov kev tiv thaiv nyhuv vim dissolution, thiab ces tag nrho corrosion tshwm sim. Txawm hais tias nws yog ib qho kev txhim kho corrosion los ntawm chemical corrosion los yog electrochemical corrosion, qhov zoo tshaj plaws yog tias nws yog ib qho nyuaj rau tsim ib qho kev tiv thaiv passivation zaj duab xis rau saum npoo ntawm cov khoom thaum lub sij hawm corrosion, thiab cov khoom corrosion yuav yaj nyob rau hauv nruab nrab, los yog tsim ib tug xoob ntxeem tau oxide, uas intensifies tus txheej txheem corrosion. Qhov kev puas tsuaj ntawm kev txhim kho corrosion tsis tuaj yeem kwv yees: ua ntej, nws yuav ua rau txo qis hauv cheeb tsam ntawm lub siab ntawm cov hlab ntsha, uas yuav ua rau perforation to, los yog rupture los yog seem vim lub zog tsis txaus; Thib ob, nyob rau hauv cov txheej txheem ntawm electrochemical kev txhim kho corrosion, H + txo cov tshuaj tiv thaiv feem ntau nrog, uas yuav ua rau cov khoom ntim nrog hydrogen, thiab tom qab ntawd ua rau hydrogen embrittle thiab lwm yam teeb meem, uas yog vim li cas cov khoom yuav tsum tau dehydrogenated. thaum welding tu.
2. Pitting yog qhov tshwm sim corrosion hauv zos uas pib ntawm cov hlau nto thiab nthuav tawm sab hauv los tsim ib lub qhov me me zoo li lub qhov corrosion. Nyob rau hauv ib qho kev nruab nrab ib puag ncig, tom qab ib lub sij hawm, tus neeg etched qhov los yog pitting tej zaum yuav tshwm sim nyob rau hauv cov hlau nto, thiab cov etched qhov yuav mus txuas ntxiv mus rau qhov tob nyob rau hauv lub sij hawm. Txawm hais tias thawj zaug hlau poob qis yuav me me, vim qhov ceev ceev ntawm lub zos corrosion, cov khoom siv thiab cov yeeb nkab phab ntsa feem ntau perforated, ua rau muaj xwm txheej ceev. Nws yog ib qho nyuaj rau kev soj ntsuam pitting corrosion vim hais tias lub qhov pitting yog me me thiab feem ntau yog them los ntawm corrosion khoom, yog li nws yog ib qho nyuaj rau kev ntsuas thiab sib piv pitting degree ntau npaum li cas. Yog li ntawd, pitting corrosion tuaj yeem suav hais tias yog ib qho ntawm feem ntau puas thiab insidious corrosion daim ntawv.
3. Intergranular corrosion yog ib lub zos corrosion phenomenon uas tshwm sim nyob rau hauv los yog nyob ze ntawm lub grain ciam teb, feem ntau yog vim hais tias ntawm qhov sib txawv ntawm grain nto thiab cov tshuaj nyob rau hauv cov tshuaj muaj pes tsawg leeg, raws li zoo raws li lub hav zoov ntawm grain ciam impurities los yog nyob rau hauv kev ntxhov siab. Txawm hais tias intergranular corrosion tej zaum yuav tsis pom tseeb ntawm qib macro, thaum nws tshwm sim, lub zog ntawm cov khoom yuav ploj mus yuav luag tam sim ntawd, feem ntau ua rau cov khoom tsis ua hauj lwm tam sim ntawd yam tsis muaj kev ceeb toom. Ntau qhov tseeb, intergranular corrosion yog yooj yim hloov mus rau hauv intergranular stress corrosion cracking, uas dhau los ua qhov kev ntxhov siab corrosion cracking.
4. Gap corrosion yog qhov tshwm sim corrosion uas tshwm sim nyob rau hauv qhov sib txawv nqaim (dav yog feem ntau ntawm 0.02-0.1mm) tsim rau ntawm cov hlau nto vim yog txawv teb chaws lub cev los yog cov qauv tsim. Cov qhov khoob no yuav tsum nqaim txaus kom cov kua dej ntws mus rau hauv thiab kaw, yog li muab cov xwm txheej rau qhov sib txawv kom corrode. Nyob rau hauv cov kev siv, flange pob qij txha, txiv ntseej compaction nto, lap joints, weld seams tsis welded los ntawm, tawg, nto pores, vuam slag tsis ntxuav thiab tso rau ntawm cov hlau nto ntawm lub teev, impurities, thiab lwm yam., tej zaum yuav ua rau qhov khoob, ua rau. qhov sib txawv corrosion. Daim ntawv no ntawm kev txhim kho hauv zos yog qhov tshwm sim thiab muaj kev puas tsuaj loj, thiab tuaj yeem ua rau kev ncaj ncees ntawm kev sib txuas ntawm cov khoom siv thiab kev nruj ntawm cov cuab yeej, ua rau cov cuab yeej tsis ua haujlwm thiab txawm tias muaj kev puas tsuaj. Yog li ntawd, kev tiv thaiv thiab kev tswj ntawm crevice corrosion yog ib qho tseem ceeb heev, thiab cov khoom siv tu thiab tu yuav tsum tau ua.
5. Kev ntxhov siab corrosion nyiaj rau 49% ntawm tag nrho cov corrosion hom ntawm tag nrho cov ntim, uas yog yus muaj los ntawm synergistic nyhuv ntawm directional kev nyuaj siab thiab corrosive nruab nrab, uas ua rau brittle cracking. Cov kab nrib pleb zoo li no tuaj yeem txhim kho tsis tau tsuas yog raws cov ciam teb, tab sis kuj los ntawm cov nplej nws tus kheej. Nrog rau txoj kev loj hlob ntawm cov kab nrib pleb mus rau sab hauv ntawm cov hlau, nws yuav ua rau muaj kev poob qis hauv lub zog ntawm cov qauv hlau, thiab txawm tias ua rau cov khoom siv hlau dheev puas tsuaj yam tsis muaj kev ceeb toom. Yog li ntawd, kev nyuaj siab corrosion-induced cracking (SCC) muaj cov yam ntxwv ntawm tam sim ntawd thiab muaj zog puas, thaum lub tawg yog tsim, nws expansion tus nqi yog ceev heev thiab tsis muaj ib qho tseem ceeb ceeb toom ua ntej qhov tsis ua hauj lwm, uas yog ib qho teeb meem heev ntawm cov khoom tsis ua hauj lwm. .
6. Qhov kawg corrosion phenomenon yog qaug zog corrosion, uas yog hais txog cov txheej txheem ntawm gradual kev puas tsuaj rau saum npoo ntawm cov khoom kom txog rau thaum rupture nyob rau hauv kev sib xyaw ua ke ntawm alternating kev ntxhov siab thiab corrosive nruab nrab. Kev sib xyaw ua ke ntawm kev xeb thiab cov khoom siv hloov pauv ua rau lub sijhawm pib thiab lub voj voog lub sijhawm ntawm kev qaug zog tawg luv luv, thiab qhov tawg nrawm nrawm nce, uas ua rau qaug zog ntawm cov ntaub ntawv hlau txo qis heev. Qhov tshwm sim no tsis tsuas yog ua kom nrawm nrawm ntawm qhov tsis ua haujlwm thaum ntxov ntawm cov khoom siv, tab sis kuj ua rau lub neej kev pab cuam ntawm lub nkoj siab tsim raws li cov txheej txheem qaug zog qis dua li qhov xav tau. Nyob rau hauv tus txheej txheem ntawm kev siv, thiaj li yuav tiv thaiv tau ntau yam corrosion phenomena xws li qaug zog corrosion ntawm stainless hlau siab hlab ntsha, yuav tsum tau ua raws li cov kev ntsuas nram qab no: txhua txhua 6 lub hlis kom huv si huv si sab hauv lub sterilization tank, dej kub tank thiab lwm yam khoom siv; Yog tias cov dej hardness siab thiab cov cuab yeej siv ntau dua 8 teev hauv ib hnub, nws raug ntxuav txhua 3 lub hlis.