First, let's look at the consequences of passivating screws without hot dip galvanizing. After the screw is galvanized, if it is stored in a humid and non-ventilated environment, the zinc layer will corrode quickly, and it will appear a white substance on the outside. We generally call this substance "white rust". This is the most intuitive way to identify whether the galvanized parts are corroded or not.
Cov laj thawj rau kev tsim cov xeb dawb: Txij li cov hlau zinc yog cov hlau nquag, nws yog qhov zoo ntawm kev ua haujlwm zinc hydroxide nrog cov dej noo hauv huab cua. Tom qab ntawd cov zinc hydroxide ntxiv cov tshuaj tiv thaiv nrog CO2 los ua cov yeeb yaj kiab uas muaj ntom nti thiab nplaum Txawm li cas los xij, ib tug loj tus naj npawb ntawm hoarded screws tiv thaiv cov hlau nto los ntawm tag nrho cov ntaub ntawv tiv thaiv zaj duab xis, thiab lub zos electrochemical tshuaj tshwm sim, uas ua rau cov tsim ntawm dawb xeb.
Passivation thiab sealing kev kho mob ntawm cov ntsia hlau tom qab kub dip galvanizing
Passivation kev kho mob yog ib hom tshuaj hloov pauv txheej kev kho mob. Cov txheej txheem passivation tiag tiag nyob ntawm cov txheej txheem electrochemical ntawm cov hlau. Nws suav nrog cov kauj ruam anodic dissolution, nyob rau hauv uas cov hlau nto yog oxidized, thiab cov txheej txheem cathodic nrog txo qee cov ions hauv cov tshuaj passivation, ua rau qis -valent ions thiab hlau corrosion khoom los ua ib zaj duab xis passive ntawm qhov chaw.
Ib zaj duab xis uas tsis muaj zog cais cov hlau los ntawm qhov nruab nrab nruab nrab, cuam tshuam cov tshuaj tiv thaiv corrosion. Cov yeeb yaj kiab tsis tiav lossis ntxeem tau, qhov twg cov tshuaj tiv thaiv corrosion tshwm sim tab sis raug cuam tshuam, uas tiv thaiv cov txheej txheem ntawm anodic dissolution thiab ua rau cov hlau nyob rau hauv lub xeev passivated.
Yog li ntawd, txhawm rau txhim kho cov txheej txheem, kev tiv thaiv ntau dua ntawm cov ntsia hlau. Cov txheej txheem passivation yuav tsum raug kaw tom qab cov txheej txheem passivation, feem ntau yog los tiv thaiv cov zaj duab xis passivation tsis tiav los ntawm kev siv tshuaj kho, thiab tiv thaiv zoo dua cov ntsia hlau los ntawm corrosion.