Galvanized Txheej Txheej Txheej Txheem: Metallurgy ntawm Kub-Dip Zinc Txheej

Txheej txheem cej luam ntawm Galvanizing Reaction

Cov txheej txheem kub -dip galvanizing ua ib qho metallurgically sib raug zoo zinc txheej ntawm cov hlau los ntawm cov tshuaj sib txawv ntawm cov hlau thiab zinc molten. Thaum cov hlau ua haujlwm tau muab tso rau hauv molten zinc ntawm li 450 degree, zinc thawj zaug ntub cov hlau huv si thiab dissolves me me ntawm cov hlau, ces hlau thiab zinc interdiffuse kom loj hlob ib ntu ntawm hlau-zinc intermetallic txheej. Nyob rau sab saum toj ntawm cov no loj hlob txheej txheej ntawm ze li ntawm cov zinc ntshiab uas muab cov khoom galvanized lawv cov yam ntxwv zoo li.

Theem 1: Tsim cov hlau-Zinc Solid Solution

Thaum lub sijhawm immersion, zinc atoms yaj mus rau saum npoo ntawm cov hlau, tsim ib qho alpha- cov kua hlau uas zinc yaj hauv lub cev -cented cubic hlau lattice. Cov txheej nyias nyias no yog lub hauv paus ntawm txheej txheej: kev sib xyaw ntawm ob lub hlau tsis yog ib qho yooj yim kho tshuab tab sis muaj tseeb metallurgical daim ntawv cog lus, uas yog vim li cas cov txheej txheej adheres zoo heev thiab muaj sia nyob khoov thiab cuam tshuam.

Theem 2: Kev loj hlob ntawm Intermetallic Phase

Thaum cov tshuaj tov yog saturated nrog zinc, ntxiv cov tshuaj tiv thaiv tshwm sim los ntawm diffusion. Zinc atoms migrate rau hauv cov hlau lattice thaum hlau atoms diffuse sab nraud rau hauv zinc molten, thiab ib tug series ntawm intermetallic compounds cov ntaub ntawv ntawm lub interface. Nyob rau hauv ib txwm kub-dip txheej txheej qauv muaj cov gamma thiab delta theem nyob ze rau cov hlau (nplua nuj nyob rau hauv hlau) thiab lub zeta theem ntxiv, txhua tus muaj ib tug yam ntxwv hardness thiab muaj pes tsawg leeg. Tag nrho cov txheej txheem intermetallic yog tawv thiab hnav- tiv taus, thaum lub txheej txheej tseem mos thiab du.

Kauj Ruam 3: Tsim Cov Txheej Txheem Ntshiab Zinc

Thaum lub workpiece raug tshem tawm ntawm lub da dej, nws nqa ib txheej ntawm molten zinc uas solidifies mus rau hauv lub sab nrauv eta theem: ib tug hexagonal kaw -packed qauv ntawm ze li ntawm ntshiab zinc nrog ib tug hlau ntsiab lus ntawm tsis ntau tshaj li 0.003%. Lub eta txheej yog qhov pom, pom qhov chaw ntawm txheej. Nws lub thickness yog tswj los ntawm kev tshem tawm ceev thiab los ntawm cov roj so hauv cov kab nruam; nyob rau hauv batch galvanizing nws yog tswj los ntawm lub immersion lub sij hawm, lub da dej kub thiab cov hlau chemistry.

Zinc Dross Formation

Tsis yog tag nrho cov hlau uas yaj hauv da dej mus txog qhov chaw ntawm lub workpiece. Ib feem reacts nrog zinc nyob rau hauv lub yaj los tsim cov intermetallic hais uas yog denser tshaj li cov zinc molten thiab dab dej mus rau hauv qab ntawm lub lauj kaub galvanizing, qhov uas lawv accumulate li hauv qab dross. Sab saum toj dross yog tsim los ntawm oxidation ntawm da dej nto. Ob daim ntawv tshem tawm zinc los ntawm kev siv tau zoo, yog li kev tswj hwm da dej, suav nrog kev tswj qhov kub thiab txias, aluminium ntxiv thiab skimming tsis tu ncua, yog qhov tseem ceeb kom cov txheej txheem zoo ruaj khov thiab zinc noj nyiaj txiag.

Cov nyhuv ntawm Steel Chemistry thiab txheej txheem sib txawv

Cov tshuaj tiv thaiv yog nyob ntawm cov ntsiab lus ntawm silicon thiab phosphorus ntawm cov hlau, vim tias cov ntsiab lus no ua rau cov hlau nrawm dua -zinc interdiffusion. Kev xyaum niaj hnub ntxiv ib qho me me ntawm txhuas rau hauv da dej, feem ntau yog 0.1-0.3% rau batch ua haujlwm, uas tsim cov txheej txheem nyias nyias uas ua rau cov tshuaj tiv thaiv hlau-zinc qeeb thiab ua rau cov txheej txheem ntau dua. Da dej kub, lub sij hawm immersion, tshem tawm ceev thiab roughness ntawm steel nto tag nrho cov cuam tshuam rau qhov kawg txheej thickness thiab qauv.

Txheej Txheem thiab Cov Khoom

Cov txheej ua tiav yog li txheej txheej txheej: nyias alpha- hlau cov kua, ib qho nyuaj intermetallic cheeb tsam (gamma, delta thiab zeta theem) uas muab adhesion thiab hnav tsis kam, thiab mos ntshiab -zinc eta txheej uas muab kev tiv thaiv corrosion thiab zoo li. Qhov kev sib xyaw no coj txawv ntawm ib qho -theem txheej: cov txheej intermetallic yog tawv thiab nkig, thaum lub eta txheej khoov thiab deforms nrog cov hlau. Rau daim ntawv cov khoom ib txheej nyias nrog ib feem me me intermetallic yog nyiam rau formability; rau cov txheej txheem txheej txheej tuab yog xaiv rau lub neej corrosion siab tshaj plaws.

Cov qauv thiab Kev Tshawb Fawb

Txheej thickness thiab loj raug txheeb xyuas raws li cov qauv khoom: ISO 1461 rau kub -dip galvanized coatings ntawm fabricated hlau thiab steel cov khoom, GB / T 13912 raws li Suav sib npaug, thiab EN 10346 los yog ISO 3575 rau nruam galvanized ntawv. Txheej thickness yog ntsuas los ntawm magnetic gauges los yog los ntawm txoj kev gravimetric, thiab adhesion yog soj ntsuam los ntawm khoov thiab kev ntsuam xyuas. Cov txheej txheem txheej tuaj yeem kuaj xyuas metallographically kom paub meej tias txhua theem muaj nyob rau hauv qhov tseeb proportions.

FAQ

Yog vim li cas galvanized hlau qhia ib spangled tsos?

Cov ntaub ntawv spangle thaum cov zinc txheej molten solidifies thiab zinc crystals loj hlob sab nraud los ntawm cov ntsiab lus nucleation. Spangle loj nyob ntawm seb tus da dej muaj pes tsawg leeg, tus nqi cua txias thiab muaj cov spangle- txhawb cov ntsiab lus hauv cov da dej ib txwm muaj.

Dab tsi yog qhov txawv ntawm eta txheej thiab cov txheej txheem alloy?

Lub eta txheej yog ze li ntawm zinc ntshiab, mos thiab ductile. Cov txheej txheem alloy hauv qab nws yog hlau-zinc intermetallic theem uas nyuaj thiab nkig, thiab lawv muab cov hlau nplaum rau cov hlau.

Vim li cas aluminium ntxiv rau galvanizing da dej?

Aluminium tsim cov txheej txheem nyias nyias ntawm cov hlau nto uas ua rau cov hlau qeeb -zinc cov tshuaj tiv thaiv, ua rau nyias nyias, zoo ib yam thiab ntau txheej txheej. Qhov no yog qhov tseem ceeb rau cov ntawv galvanized uas yuav tsum tau yob - tsim lossis sib sib zog nqus - kos.

Yuav ua li cas zinc dross tshem tawm ntawm lub lauj kaub?

Hauv qab dross raug tshem tawm ib ntus los ntawm kev ua haujlwm skimming lossis kev siv lub tshuab thaum lub lauj kaub tau txais kev pabcuam, thiab cov dross sab saum toj yog skimmed tsis tu ncua thaum lub sijhawm tsim khoom. Kev tswj qhov kub thiab txias zoo txo ​​qhov tsim tawm.

galvanized txheej thickness tau teev los ntawm tus neeg siv khoom?

Yog lawm. Cov qauv khoom lag luam txhais cov chav kawm txheej txheej los ntawm huab hwm coj ib square meter, thiab cov neeg siv khoom qhia cov chav kawm tsim nyog rau ib puag ncig thiab kev pabcuam lub neej, piv txwv li Z275 rau kev siv sab nraum zoov.

Vim li cas cov txheej txheem ntawm batch-galvanized steel zoo li tuab dua li ntawm daim ntawv?

Batch galvanizing ntawm fabricated cov khoom siv ntev immersion lub sij hawm tsis so, yog li cov intermetallic thiab eta txheej loj hlob thicker. Nruam cov kab ntawv tswj cov thickness precisely nrog cua riam, muab ib tug thinner, ntau uniform txheej.