1.Dab tsi yog "stretch marks"? Dab tsi yog lub hauv paus ua rau lawv tsim?
"Strech marks," cov kws tshaj lij hu ua Lüders bands lossis cov txiaj ntsig txuas ntxiv, xa mus rau cov hlua khi los yog cov qauv uas tshwm sim rau saum npoo ntawm cov ntawv txias -rolled steel los xij tom qab stamping lossis stretching deformation, tsim ntawm ib lub kaum sab xis rau kev ncab. Muaj ob lub ntsiab lus tseem ceeb rau nws txoj kev tsim:
Internal ua rau (khoom siv yam khoom): Yog hais tias txias - dov coils yog siv ncaj qha tom qab annealing, lawv muaj interstitial carbon thiab nitrogen atoms yaj nyob rau hauv interstitial qhov chaw. Cov atoms zoo li agglomerate nyob ib ncig ntawm dislocations, tsim "Cobbler gas clusters" uas pin cov dislocations. Thaum stamping pib, yuav tsum muaj kev ntxhov siab ntau dua kom tsis txhob muaj kev cuam tshuam. Thaum tso tawm, tam sim ntawd, qhov tsis sib xws ntawm cov yas deformation tshwm sim, ua rau pom Lüders bands ntawm qhov chaw.
Cov xwm txheej sab nraud (txoj kev ntxhov siab): Qhov kev tsis zoo no yog tshwm sim thaum cov nyiaj stamping deformation tshwm sim nyob rau hauv qhov tsis sib xws yielding theem ntawm cov khoom.
2.Dab tsi yog qhov kev ntsuas tseem ceeb tshaj plaws thaum lub caij txias -rolled coil ntau lawm?
Lub hauv paus ntsiab lus: Los ntawm kev siv tus nqi txo me me ntawm 0.8% mus rau 1.2% (feem ntau ua tiav los ntawm kev tswj lub elongation) rau cov ntaub mos mos, ib qho zoo li qub thiab feeb yas deformation yog ua ntej -induced. Qhov no ua ntej - deformation tso cai rau cov dislocations kom tawg tawm ntawm pinning ntawm interstitial atoms thiab rov qab mus rau lub xeev txav tau yooj yim. Nyob rau hauv txoj kev no, cov khoom tuaj yeem hloov pauv ntawm elastic deformation mus rau cov yas deformation thaum lub sij hawm tom qab stamping, tshem tawm sai sai yield plateaus thiab yog li tshem tawm stretch marks.
Qhov tseem ceeb Parameter: Lub flattening elongation yuav tsum tau tswj kom meej. Yog hais tias qhov elongation tsis txaus (xws li, los ntawm kev txo cov dov quab yuam nyob ze ntawm lub vuam kom tsis txhob muaj nws), lub yield plateau yuav tsis raug tshem tawm tag nrho, uas ua rau cov qhab nias tom qab stamping.
3.Yog hais tias cov txheej txheem leveling tiav lawm, puas muaj lwm yam uas yuav ua rau stretch marks? Piv txwv li, qhov muaj pes tsawg leeg ntawm cov khoom?
Yog lawm, kev tswj kev sib xyaw yog qhov tseem ceeb. Txawm hais tias muaj cov txheej txheem ua kom tiav, cov ntsiab lus siab interstitial atom (carbon thiab nitrogen) hauv cov hlau tuaj yeem ua rau muaj kev laus zuj zus ntxiv thiab ua rau muaj kev pheej hmoo ntawm tensile tawg.
Kev tswj los ntawm qib steelmaking: Kev tswj nruj ntawm cov pa roj carbon thiab nitrogen cov ntsiab lus hauv cov hlau molten yog tsim nyog, nrog rau kev sib ntxiv ntawm cov khoom tsim nyog ntawm cov khoom siv xws li titanium thiab niobium los ua ke nrog interstitial atoms thiab tsim cov carbonitrides ruaj khov. Qhov no txo qis cov pa roj carbon monoxide thiab nitrogen atoms yaj hauv cov matrix, uas txo qis lub peev xwm los tsim Cotillard atmospheres.
Kev sib koom ua ke ntawm cov txheej txheem Annealing: Parameters ntawm cov txheej txheem nruam annealing (xws li annealing kub thiab txias tus nqi) kuj cuam tshuam rau qhov kawg microstructure thiab cov khoom. Cov kev ntsuas no yuav tsum tau ua kom zoo ua ke nrog cov txheej txheem qib kom ntseeg tau tias cov qauv microstructure tsis muaj qhov elongation.
4.Yog tias koj ntsib cov qhab nia thaum lub sij hawm stamping, dab tsi ntawm cov txheej txheem koj tuaj yeem kho tau?
Txheeb xyuas qhov chaw ntawm cov khoom siv raw: Cov qhab nia feem ntau ua kom pom tseeb thaum pib lossis xaus ntawm cov hlau kauj vim tias cov chaw no yog qhov chaw uas lub tshuab ua haujlwm tau txiav txim siab dov quab yuam kom tsis txhob muaj cov hlua khi ntawm cov hlau zeb ntau lawm, uas ua rau cov elongation tus nqi qis dua rau qhov kev ncua deb ua ntej thiab tom qab vuam. Yog tias koj qhov chaw stamped tshwm sim los ntawm cov chaw no, cov teeb meem yuav tshwm sim.
Kho cov txheej txheem stamping:
Ua kom lub zog tsis muaj zog kom tsim nyog: Qhov no tuaj yeem hloov pauv qhov kev ntxhov siab ntawm cov khoom siv thiab qee zaum ua rau cov tsos ntawm Lüders bands.
Ua ntej- kev kho deformation: Rau cov khoom me me ntawm qhov tseem ceeb, xav txog me ntsis ua ntej -stretching los yog ua ntej- khoov cov ntawv hlau ua ntej stamping kom ua tiav cov txiaj ntsig zoo sib xws rau qib.
Hloov batch lossis coil tooj: Yog tias qhov teeb meem tshwm sim ntawm tus lej tshwj xeeb, sib txuas lus nrog tus neeg muag khoom los hloov nws.
5.Yog qhov teeb meem twb tshwm sim lawm, puas muaj kev kho mob?
Rau cov khoom stamped: Cov cim me me thiab me me tuaj yeem raug txo qis lossis tshem tawm los ntawm kev ntxiv cov txheej txheem saum npoo (xws li dhau los ntawm cov xovxwm dua lossis nto sib tsoo). Txawm li cas los xij, cov qhab nia hnyav hnyav yuav ua rau qhov tsis siv tau.
Rau cov tsis siv steel coils (rework): Yog hais tias nws tau lees paub tias cov qoob loo toj roob hauv pes tsis raug tshem tawm vim qhov tsis txaus theem ntawm lub kauj, txoj kev xav, cov txheej txheem me me (txheej txheem elongation tswj hom) tuaj yeem ua rau ntawm cov kab nqes qis los yog theem kab nrog cov xwm txheej tsim nyog los tshem tawm cov yield plateau. Piv txwv li, muaj cov xwm txheej uas qhia tau hais tias los ntawm kev siv lub zog dov tas li ua ke nrog cov txheej txheem ntub dej, cov ntawv tsis zoo corrugated tuaj yeem rov ua haujlwm rau hauv cov khoom tsim nyog.
Txiav tawm qhov pib thiab xaus: Txoj kev yooj yim tshaj plaws thiab ncaj qha tshaj plaws yog kom txiav tawm ntau qhov pib thiab xaus thaum lub sij hawm uncoiling thiab blanking, zam cov cheeb tsam uas qhov leveling elongation tsis ruaj khov thaum lub sij hawm steel zeb ntau lawm.