1.Dab tsi yog qhov laj thawj tseem ceeb ntawm kev npaj txhij txog blackening?
Residual rolling oil/emulsion carbonization: Yog hais tias lub strip nto tsis huv si ua ntej annealing, residual dov roj los yog emulsion yuav decompose thiab carbonize nyob rau hauv lub siab - kub annealing rauv, tsim nrees adhering dub los yog greyish - cov roj dub.
Dej stains / xeb:
Dej stains: Yog hais tias lub strip nto tsis tag qhuav tom qab pickling los yog tu, residual noo noo evaporates, tawm hauv mineral residue uas tsim watermarks, tej zaum kuj tsaus xim.
Xeb: Yog hais tias ya raws (xws li dej los nag los yog condensation) nyob rau hauv thaum lub sij hawm coiling, uniform los yog strip -zoo li tus liab liab hlau oxide (Fe₂O₃) yuav tsim thaum lub sij hawm cia, zoo li yog "blackened".
Oxidation:
oxidation me ntsis: Hauv qhov chaw ntub dej, ib daim oxide zaj duab xis nyias nyias ua rau ntawm qhov chaw, muaj peev xwm nthuav tawm cov xim cuam tshuam (xiav-liab lossis daj tsaus).
oxidation hnyav: Yog tias raug corrosive media xws li acids los yog ntsev, los yog nyob rau hauv lub sij hawm siab - kub thiab siab - av noo ib puag ncig, ib tug thicker oxide nplai (Fe₃O₄, thiab lwm yam) yuav tsim, tshwm dub los yog xim av tsaus.
2.Dab tsi yog txoj hauv kev los tuav thiab tiv thaiv qhov no?
Kev kho mob:
Txoj kev siv lub cev: Rau me me, xoob paug paug, qhuav (xws li, txhuam, sandblasting) los yog ntub dej (piv txwv li, siab- ntxuav dej siab) yuav siv tau. Txawm li cas los xij, rau cov kab mob uas muaj carbonized los yog tsim cov txheej oxide tuab, kev tshem tawm tiav yuav nyuaj thiab kim.
Cov txheej txheem tshuaj: Acid pickling (xws li hydrochloric acid, sulfuric acid) tuaj yeem tshem tawm cov txheej txheem oxide, tab sis nws hloov kho qhov chaw thiab qhov ntev ntawm lub substrate, feem ntau yuav tsum tau rerolling lossis kho raws li cov khoom puas.
Kev Tiv Thaiv (Critical):
Txhim khu kev tu: Ua kom muaj kev tu zoo tom qab dov, tswj cov concentration, kub, thiab tshuaj tsuag siab ntawm cov tshuaj ntxuav.
Xyuas kom qhuav: Tom qab ntxuav thiab ua ntej oiling, lub sawb saum npoo yuav tsum tau kom qhuav kom huv si siv cov khoom kom qhuav.
Tswj Oiling: Siv cov xeb tsim nyog- tiv thaiv roj thiab xyuas kom meej txawm tias daim ntawv thov thiab cov roj ua tiav.
Txhim Kho Cia: Cov tsev khaws khoom yuav tsum zoo- qhov cua, qhuav, thiab khaws cia ntawm qhov kub thiab av noo tas li kom tsis txhob muaj qhov sib txuam. Siv cov ntoo thaiv thaum stacking steel coils kom tsis txhob muaj kev sib cuag nrog hauv av.
3.Dab tsi yog qee qhov kev mob siab rau saum npoo blackening kev kho mob?
Phosphating Blackening (Dub Phosphating):
Lub hauv paus ntsiab lus: Hlau yog immersed nyob rau hauv ib tug acidic phosphate tov uas muaj manganese, hlau, thiab zinc. Cov tshuaj tiv thaiv ua rau cov xim dub crystalline rau ntawm qhov chaw, feem ntau yog tsim los ntawm ferric manganese phosphate.
Yam ntxwv:
Zaj duab xis yog greyish -dub mus rau dub ntshiab, zoo ib yam thiab zoo nkauj txaus nyiam.
Cov yeeb yaj kiab muaj cov qauv microporous, cov khoom zoo adsorption, thiab feem ntau siv ua ke nrog roj, muab kev tiv thaiv xeb zoo heev.
Nws txhim kho qhov adhesion ntawm cov txheej tom ntej.
Cov yeeb yaj kiab nws tus kheej kuj muaj qee qhov kev sib txhuam-txo thiab hnav- cov khoom tiv taus.
Daim ntaub ntawv: Automotive qhov chaw, fasteners, phom, khoom siv kho qhov muag, thiab lwm yam.
Alkaline Oxidation Blackening (Xiav):
Lub hauv paus ntsiab lus: Nyob rau hauv qhov kub ntawm - kub (kwv yees li 135-155 degree) concentrated alkali (sodium hydroxide) thiab oxidant (sodium nitrite) tov, ib txheej tuab ntawm hlau (III) oxide (Fe₃O₄) zaj duab xis cov ntaub ntawv ntawm cov hlau nto.
Yam ntxwv:
Cov xim feem ntau yog xiav -dub lossis tsaus dub, nrog rau qhov ua tiav.
Cov zaj duab xis yog nyias heev (li 0.5-1.5 micrometers) thiab tsis cuam tshuam qhov loj ntawm ib feem.
4.Qhov txheej txheem ntws yog dab tsi?
Rau txias- dov coils, ib txoj kab ua haujlwm tas mus li feem ntau yog siv: degreasing → dej ntxuav → pickling (xeb tshem tawm thiab ua kom) → dej ntxuav → blackening kev kho mob (phosphating los yog oxidation da dej) → dej ntxuav → sealing (xws li passivation los yog oiling) → ziab.
5.Yuav txiav txim siab li cas?
Saib seb qhov "blackening" yog ib yam thiab glossy, los yog mottled thiab stained. Nws puas tuaj yeem muab tshem tawm? Yog tias nws tsis sib xws, nws yog qhov xwm txheej ib qho (tsis xws luag), thiab qhov ua rau yuav tsum tau pom nyob rau hauv cov theem tsim khoom thiab khaws cia. Yog hais tias ib tug uniform, ua hauj lwm dub zaj duab xis yog yuav tsum tau, nws yog ob (txheej txheem).
Qhia meej txog qhov yuav tsum tau ua: Yog tias xav tau kev ua haujlwm blackening, qhia meej:
Kev siv kawg: Puas yog tsom rau kev tiv thaiv xeb, hnav tsis kam, lossis zoo nkauj?
Cov txheej txheem tom ntej: Puas yog txheej txheej, kos duab, thiab lwm yam, xav tau?