Q: Puas yog qhov nyuaj ntawm galvanized coils cuam tshuam rau zinc txheej?
A: Yog, nws ua. Lub toughness ntawm galvanized coils- uas yog, cov khoom muaj peev xwm nqus cov yas deformation zog ua ntej tawg- tsis yog tsuas yog txiav txim los ntawm cov hlau substrate. Lub xub ntiag ntawm zinc txheej hloov lub zuag qhia tag nrho toughness ntawm galvanized kauj nyob rau hauv ntau txoj kev. Cov kev tshawb fawb tau pom tias piv rau tib lub substrate, kub -dip galvanized steel los xij pom tias muaj zog tensile thiab yas deformation muaj peev xwm. Kev txo qis hauv plasticity feem ntau yog los ntawm microcracks tsim ntawm lub substrate nto thaum kub -dip galvanizing, thaum lub zog poob yog vim qhov qis zog ntawm cov zinc txheej piv rau cov hlau substrate. Tsis tas li ntawd, cov txheej txheem sib txawv (ntshiab zinc txheej, zinc- hlau alloy txheej) muaj qhov sib txawv ntawm qhov toughness. Yog li ntawd, thaum ntsuas qhov toughness ntawm galvanized coils, zinc txheej yuav tsum raug xam tias yog ib qho kev ywj pheej thiab tsis tuaj yeem sib npaug nrog qhov toughness Performance index ntawm substrate.
2. Dab tsi yog qhov cuam tshuam ntawm intermetallic compounds hauv zinc-hlau alloy coatings ntawm toughness?
A: Zinc- hlau alloy coatings muaj ntau txheej nyias ntawm hlau-zinc intermetallic tebchaw, suav nrog Γ theem, Γ1 theem, δ theem, thiab ζ theem. Cov tebchaw no feem ntau yog tawv thiab nkig, thiab yog qhov laj thawj tseem ceeb rau kev txo qis ntawm cov galvanized coils. Ntawm lawv, lub innermost Γ theem, ze tshaj rau lub substrate, yog ib tug nkig theem thiab muaj qhov zoo tshaj plaws rau txheej adhesion; lub thicker lub Γ theem, qhov yooj yim nws yog pulverize thiab tev tawm. Cov theem Γ1 uas nyob ib sab, txawm tias nws tuaj yeem cuam tshuam qhov kev nthuav tawm sab nraud ntawm cov kab nrib pleb, nws tus kheej me ntsis nkig. Daim phiaj-zoo li δ theem nyob rau hauv nruab nrab muaj cov yas zoo thiab yog ib qho ntawm ob peb qhov tawv nqaij- pab txheej txheej hauv txheej txheej. Sab nrauv ζ theem yog nquag tawg thaum lub sij hawm deformation thiab propagates raws theem ciam teb. Qhov sib txawv loj hauv plasticity ntawm cov theem hauv cov txheej txheej alloy ua rau muaj kev ntxhov siab nyob rau hauv lub txheej thiab ntawm txheej txheej / hlau substrate cuam tshuam vim qhov sib txawv ntawm deformation thaum lub sij hawm stamping, ua rau kom ntxov ntxov tawg ntawm txheej thiab txo qhov toughness ntawm galvanized kauj thaum khoov, sib sib zog nqus nqus, thiab lwm yam kev ua.
3. Yuav ua li cas microcracks tsim thaum lub sij hawm galvanizing txheej txheem rau toughness?
A: Qhov kub-dip galvanizing txheej txheem nws tus kheej qhia microcracks rau hauv zinc txheej thiab substrate nto. Cov kab nrib pleb no dhau los ua cov ntsiab lus kev ntxhov siab, ncaj qha thiab tsis zoo cuam tshuam rau lub zog. Kev tshawb fawb nthuav tawm ntau yam -theem txoj hauv kev rau kev pib tawg thiab nthuav tawm: Ua ntej, vim muaj kev ntxhov siab seem, microcracks tsim nyob rau hauv siab - kub σ-FeZn10 txheej; Thaum raug rau sab nraud tensile kev nyuaj siab, cov kab nrib pleb propagate upwards raws lis ciam teb nyob rau hauv no txheej; Tom qab ntawd, cov kab nrib pleb hloov mus rau ζ-FeZn13 txheej thiab txuas ntxiv nthuav tawm raws FeZn13-Zn theem interface; Thaum kawg, lawv rov nthuav dav ntxiv raws li cov ciam teb hauv thaj av η-Zn txheej kom txog thaum txheej txheej tawg tag. Qhov no multi-theem crack propagation hom los ntawm lub sab hauv nkig theem mus rau sab nraud txhais tau hais tias txawm ua ntej tag nrho cov kev ntxhov siab mus txog lub substrate yield zog, txheej tawg tau tsim thiab propagated. Rau cov galvanized coils uas yuav tsum tau rov khoov los yog sib sib zog nqus nqus, cov microcracks no yuav nrawm propagation thaum lub sij hawm loj deformations thiab txawm txuas mus rau hauv lub substrate, heev tsis muaj zog cov ntaub ntawv lub toughness reserves thaum lub sij hawm kev pab cuam.
4. Puas yog zinc txheej ua rau hydrogen embrittlement hauv galvanized coils?
A: Yog. Hydrogen embrittlement yog ib qho tseem ceeb mechanism uas lub toughness ntawm galvanized coils raug cuam tshuam los ntawm zinc txheej, tshwj xeeb tshaj yog nyob rau hauv marine atmospheres los yog ib puag ncig ntub. Yog tias cov zinc txheej raug puas thaum lub sijhawm ua haujlwm, nws muab kev tiv thaiv cathodic rau cov hlau substrate. Txawm li cas los xij, kev tiv thaiv tsis zoo ntau dhau tuaj yeem ua rau hydrogen evolution ntawm steel nto. Hydrogen atoms nkag mus rau hauv lub matrix lattice, ua rau muaj kev txo qis hauv cov khoom toughness. Cov kev tshawb fawb qhia tau hais tias hydrogen permeation nyob rau hauv seawater ho txo qhov elongation tom qab tawg thiab lub zog ceev ntawm kub-dip galvanized steel, hloov nws fracture hom los ntawm ductile fracture mus rau quasi-cleavage brittle fracture. Raws li lub sijhawm ua haujlwm nce ntxiv, cov ntsiab lus hydrogen hauv cov khoom txuas ntxiv nce, thiab hydrogen embrittlement rhiab heev kuj nce. Qhov no yog vim li cas siab -lub zog lub caij nplooj ntoos hlav ntxhua khaub ncaws, fasteners, thiab lwm yam, feem ntau yuav tsum tau tshwj xeeb hydrogen tshem tawm cov cua sov kho tom qab galvanizing (feem ntau tuav ntawm 190 ~ 230℃rau 6 ~ 8 teev) kom txo tau txoj kev pheej hmoo ntawm brittle puas.
5. Dab tsi yog qhov tseem ceeb cuam tshuam rau qhov toughness ntawm galvanized coils? Lawv yuav zam tau li cas?
A: Cov yam ntxwv cuam tshuam rau lub zog ntawm cov galvanized coils tuaj yeem raug faib ua feem ntau raws li hauv qab no: Ua ntej, txheej thickness thiab hom- tuab zinc txheej, ntau dua qhov kev pheej hmoo ntawm tawg pib thiab nthuav tawm; alloyed coatings, vim muaj cov tawv thiab nkig intermetallic tebchaw, feem ntau muaj qis toughness dua cov ntshiab zinc txheej. Thib ob, substrate muaj pes tsawg leeg- cov ntsiab lus thiab qhov sib piv ntawm cov khoom xws li silicon thiab manganese hauv substrate cuam tshuam rau kev xaiv oxidation tus cwj pwm thaum lub sij hawm annealing. Thaum lub sij hawm ζ theem ntawm cov ntaub ntawv ntawm lub interface, lub interface yog nquag mus tawg thaum lub sij hawm kuaj tensile, thiab cov kab nrib pleb propagate mus rau hauv lub substrate, ua rau ib tug txo nyob rau hauv toughness. Thib peb, cov txheej txheem tsim khoom-kub-dip galvanizing kub, lub sijhawm immersion, thiab cov txheej txheem alloying tag nrho cuam tshuam rau cov tuab thiab kev faib tawm ntawm txhua theem hauv txheej txheej, yog li hloov cov kev ua haujlwm toughness. Txhawm rau kom tsis txhob degradation toughness, cov kev ntsuas hauv qab no raug pom zoo: xaiv cov txheej txheej tsim nyog raws li cov txheej txheem ua tiav (thaum ua ntej cov zinc coatings ntshiab tshaj cov txheej txheej rau sib sib zog nqus- kos duab qhov chaw); nruj me ntsis tswj zinc txheej thickness kom tsis txhob dhau kev tsim tshwj xeeb; optimize substrate muaj pes tsawg leeg los suppress tsim ntawm unfavorable interfacial brittle theem; thiab rau siab -lub zog galvanized qhov chaw, ntxiv cov txheej txheem kev tshem tawm hydrogen thaum tshav kub kub los tiv thaiv hydrogen{10}}induced embrittlement.