Corrosion yog qhov tshwm sim uas ib qho khoom siv uas undergoes ib qho tshuaj tiv thaiv kev siv tshuaj lossis hluav taws xob nrog cov khoom ib puag ncig, uas ua rau muaj kev sib tawg. Txawm hais tias nyob rau hauv peb lub neej txhua hnub, lossis hauv kev lag luam kev lag luam, hlau "xeb" tuaj yeem pom txhua txhia qhov txhia chaw, dav hlau, dav hlau thiab lwm yam xeb. Corrosion yuav tsis tsuas yog ua rau kev ua lag luam nyiaj txiag, thiab txawm tias ua rau kev nyab xeeb kev nyab xeeb, qhov tseem ceeb ntawm kev tiv thaiv corrosion yuav tsum tsis txhob tawm tsam.
Nyob rau hauv ciam teb txheej ntawm substrate, thawj txheej txheej txheem yuav tsim tawm. Vim yog cov pa oxygen nyob rau hauv cov huab cua, txheej ntawm cov kev xav feem ntau muaj nyob rau hauv daim ntawv ntawm ib qho oxide thiab yog li ntawd tseem hu ua thawj oxide zaj duab xis (pour). Cov txheej no feem ntau yog yooj yim thiab pib tiv thaiv kev xeb ntxiv.
Nyob rau sab saum toj ntawm txheej kev cuam tshuam, cov tshuaj suav hauv cov khaubncaws sab nraud pov tseg. Feem ntau yog thawj tus yog dej, uas, vim yog cov pab pawg neeg hlau uas muaj cov tshuaj tiv thaiv hydroxide Cov txheej no yog cov txheej chemisorption, uas yog qhov muaj zog ua txhua yam thiab nyuaj rau rov yaj. Lub txheej chemisorption yog ze ze los ntawm cov txheej txheem adsorption ib qho, uas muaj cov tawv nqaij tsis zoo thiab hloov tau yooj yim.
Thawj zaj duab xis oxide yog qhov tseem ceeb tshaj plaws txheej ntawm corrosion tsis kam, cov tuab ntawm zaj duab xis, tus muaj zog dua adhesion, ntau corrosion tsis kam. Hauv lwm lo lus, kev tiv thaiv corrosion yuav tsum tau pib thaum tsim thiab ruaj khov ntawm thawj oxide zaj duab xis (pof). Nyob ntawm cov khoom siv hlau, cov tshuaj ntxiv (piv txwv li surfactants, redeb cov neeg sawv cev) yuav tsum muaj. Corrosion feem ntau pib nrog kev txiav txim siab ntawm thawj cov yeeb yaj kiab oxide, tab sis nyob rau hauv unalloy oxide zaj duab xis yog qhov ruaj khov dua vim muaj kev sib dhos (tshwj xeeb yog cov chromium).
Hom kev txhim kho hauv lub neej muaj ntau hom sib txawv ntawm kev hais tawm, cia saib cov xya hom hauv qab no.
1. Vision corrosion:Cov hlau yuav raug yaig yuav luag mus ib txhis rau saum npoo. Nws yog daim ntawv feem ntau ntawm kev corrosion thiab feem ntau yog tshwm sim los ntawm cov cua lossis qias neeg.
2. Crevice corrosion:Cov teeb pom kev ntawm cov hlau lossis cov tswv yim tuaj yeem ua rau muaj kev mob corrosion vim tias cov electrolyte tau khaws cia los ntawm capillary kev ua thiab tej zaum yuav ua kom muaj kev sib txawv ntawm kev sib txawv. Qhov no tuaj yeem tiv thaiv los ntawm kev ntsuas tsim nyog.
3. Hu rau corrosion:Electrochemical corrosion tshwm sim los ntawm ob qho kev sib cuag sib cuag thaum ib leeg hauv electrolyte, nrog ib qho ntawm cov hlau corroding ntawm ib tus nqi sai sai. Nws tuaj yeem tiv thaiv los ntawm xaiv cov ntaub ntawv tsim nyog lossis cuam tshuam qhov kev ua haujlwm ntawm cov ntaub ntawv.
4. Pitting:Pitting ua rau pitting, cratering lossis pinpointing. It is usually caused by pitting damage to the protective layer, such as pores in the coating or chloride erosion on the passivation layer.
5. Qib inregranular:Mas tsuas yog Ferrite CR thiab Crni Austenitic steel nyob rau hauv cov ciaj ciam av yog eroded, no corrosion yuav ua rau cov qoob loo ntawm cov nplej tsis muaj zog heev. Kev mob siab cuam tshuam corrosion tuaj yeem ua rau cov hlau tsis muaj zog thiab duclling lub zog, tsim nyog kev kho cua sov yog los tiv thaiv kev txhim kho kev txhim kho kev txhim kho ntawm lub ntsej muag.
6. LW-point corrosion:Lew-point corrosion yog hais txog lub zog khov kho vim yog cov hlau uas muaj zog, thiab crni steel hlau, yuav tsum tau tiv thaiv los ntawm ib txheej tiv thaiv kev tiv thaiv zoo.
7. Kev ntxhov siab corrosion tawg:Hauv corrosive media, thaum nyob rau hauv cov ntaub ntawv kev ntxhov siab, tshwj xeeb tshaj yog nyob rau hauv cni antustenic steel nyob rau hauv kev ntxhov siab corrosion tawg.
Lub Sijhawm Post: Lub Tsib Hlis-21-2024