59. Cov hlau hauv zinc da dej cuam tshuam li cas kub -dip galvanizing?

Hlau (Fe), nrog ib tug txheeb ze atomic mass ntawm 56, zoo li silvery -dawb. Cov hlau ntshiab muaj qhov melting point ntawm 1535℃thiab qhov kub ntawm 3000 degree. Nyob rau hauv molten zinc, hlau feem ntau yog los ntawm peb qhov chaw: (1) kev kis kab mob los ntawm cov zinc remelted nrog cov ntsiab lus hlau ntau dua; (2) ζ-theem tsim los ntawm kev cuam tshuam ntawm cov kav dej steel, galvanized steel pots, thiab steel machinery nrog molten zinc; thiab (3) zinc slag tsim thaum hlau ntsev adhered rau steel kav tom qab acid pickling react nrog molten zinc. Raws li cov lus ceeb toom, ib feem ntawm cov ntsev hlau tuaj yeem ua rau muaj nees nkaum- tsib feem ntawm zinc.
Qhov siab dua cov ntsiab lus hlau hauv zinc da dej, ntau zinc residue raug tsim, ua kom cov viscosity ntawm zinc da dej. Qhov no txo ​​qhov fluidity ntawm zinc ntws, ua rau cov txheej tuab (feem ntau η-theem), zinc plating nkig tsis yooj yim, dull grey nto, thiab cov tsos ntxhib. Tshwj xeeb tshaj yog, thaum zinc muaj cov hlau ntawm qib mus txog ob peb kaum - txhiab, nws ua rau cov zinc txheej hardness thiab cuam tshuam cov txheej txheem recrystallization. Ntawm cov ntsiab lus hlau ntawm 0.02%, lub neej ntev ntawm zinc plating ua luv luv (raws li zinc ua raws li cov anode). Txhawm rau hais qhov no, feem ntau yog aluminium lossis silicon ntxiv kom tshem tawm cov hlau. Yog li, cov txheej txheem zinc plating txheej txheem tau teev tseg tias cov ntsiab lus hlau hauv zinc da dej los ntawm qhov chaw mus rau qhov tob ua haujlwm yuav tsum tsis pub tshaj 0.05% (sib npaug rau Zn-4 txog Zn-5). Kev siv cov zinc remelted yog txwv tsis pub thaum nws cov ntsiab lus hlau nce mus txog 0.2%. Kev sim cov ntaub ntawv qhia tau hais tias ntawm 450 degree, zinc plating hnyav nce mus rau 330 grams ib square meter ntawm 0.06% hlau ntsiab lus, thiab nce mus rau 450 grams ib square meter ntawm 0.25% hlau ntsiab lus. Qhov no ua rau pom kev siv zinc ntau ntxiv. Hlau nyob rau hauv zinc da dej tsuas yog cuam tshuam rau cov ntshiab zinc txheej theem thiab tsis muaj kev cuam tshuam tseem ceeb ntawm cov tshuaj tiv thaiv hlau-zinc.