Cov txheej txheem kho qhov chaw ntawm cov ntsia hlau

Cov ntsia hlau feem ntau siv cov txheej txheem kho qhov chaw yogKev kho deg: oxidation, electrophoresis, electroplating, Dacromet plaub pawg, cov hauv qab no yog feem ntau yog ntsia hlau rauxim ntawm kev kho qhov chaw ntawm kev faib tawm cov ntsiab lus.

• Dub oxide：

Muab faib ua qhov kub thiab txias dub thiab kub siab dub, rau qhov kub thiab txias dub ua piv txwv ntawm cov txheej txheem yog: tshuaj degreasing - ntxuav dej kub - ntxuav dej txias - tshem tawm xeb thiab acid etching - ntxuav - dub - ntxuav - roj ntau dhau lossis kaw dhau. Nws yog ib txheej ntawm oxide zaj duab xis tsim los ntawm sodium hydroxide thiab sodium nitrite ntawm qhov kub siab tshaj 100 degrees.

Lub ntsiab tivthaiv ntawm cov yeeb yaj kiab oxide yog hlau tetraoxide (Fe3C4), qhov sib npaug ntawm cov yeeb yaj kiab tsuas yog 0.6-1.5um, kev tiv thaiv corrosion tsis zoo, yog tias tsis tshaj cov roj lossis kaw cov ntsev nruab nrab tsuas yog 1-2 teev lossis li ntawd, hla cov roj hauv 3-4 teev lossis li ntawd. Cov khoom siv me me tsis siv cov txheej txheem no rau lub sijhawm no. Qhov sib txawv ntawm cov xim, cov oxide dub thiab zinc dub thiab electrophoretic dub kaw, tab sis tsis ci li zinc dub thiab electrophoretic dub xim.

• Galvanized：

Kev siv hluav taws xob dub muaj ob hom zinc dub thiab nickel dub, lub hauv paus ntsiab lus ntawm cov txheej txheem yog tib yam, tsuas yog kev tsim cov tshuaj electroplating thiab kev kho tom qab nrog cov kua sib txawv lossis cov kua passivation. Zinc yog cov tshuaj lom neeg ua haujlwm, yooj yim rau oxidize thiab tsaus ntuj hauv huab cua, thiab thaum kawg tsim 'xeb dawb' xeb, zinc plating tom qab chromate kho kom npog ib txheej ntawm zinc ntawm cov yeeb yaj kiab hloov pauv tshuaj, yog li cov hlau nquag nyob hauv lub xeev passive, yog passivation ntawm zinc txheej. Passivation zaj duab xis los ntawm qhov tsos tuaj yeem faib ua dawb passivation (zinc dawb), lub teeb xiav (zinc xiav), dub passivation (zinc dub), tub rog ntsuab passivation (zinc ntsuab) thiab lwm yam.

• Electrophoresis Dub：

Siv txoj kev electrochemical los tso cov khoom colloidal ntawm cov organic resin rau ntawm qhov chaw los ua cov txheej txheem txheej organic ntawm ntau yam xim, electrophoresis dub siv ntau dua hauv kev lag luam, piv txwv li cov txheej txheem dub: degreasing-ntxuav-phosphating-electrophoresis pleev xim-qhuav. Muaj peev xwm muab faib ua anodic electrophoresis (resin ionisation rau hauv cov ions tsis zoo) thiab cathodic electrophoresis (resin electrophoresis rau hauv cov ions zoo), thiab cov txheej txheem pleev xim piv rau kev ua haujlwm tsim kho yog qhov zoo, kev ua qias tuaj thiab kev puas tsuaj rau ib puag ncig kom txo nws qhov kev tiv thaiv rau kev ua haujlwm ntsev tsis muaj zog hauv 300 teev lossis ntau dua, tus nqi thiab kev tiv thaiv corrosion zoo ib yam li Dacromet txheej txheem.

• Zinc dawb：

Cov txheej txheem electroplating yog: degreasing - ntxuav - tsis muaj zog acid activation - electroplating zinc - ntxuav - dawb passivation plaub hau - ntxuav - ziab, thiab dub zinc qhov sib txawv yog tsis muaj Over lat rack thiab passivation daws qhov sib txawv, dawb passivation yog xim tsis muaj pob tshab zinc oxide zaj duab xis, yuav luag tsis muaj chromium, yog li qhov corrosion tsis kam piv rau dub zinc, xiav zinc, xim zinc yog qhov tsis zoo, tus qauv kev lag luam hauv 6-12 teev, muaj qhov chaw tsim khoom plating no los ntawm kev txhim kho qhov tseeb ntawm qhov piv ntawm cov kua passivation tuaj yeem ua tau los tiv thaiv cov ntsev tsis muaj zog rau li 20 teev.

Vim yog cov txheej txheem kho kom zoo nkauj ntawm cov ntsia hlau, cov hlau zinc dawb yuav tsum tau ua qhov kev sim tshuaj tsuag ntsev tsis muaj zog, thiab thawj zaug pom cov xeb dawb, liab thiab xeb ntawm cov hlau zinc saum npoo ntawm cov hlau zinc li ntawm 40 teev, yog li cov xeb dawb zinc zoo dua li cov hlau npib tsib xee dawb. Cov tsos thiab cov xeb dawb zinc piv rau cov xim tsaus, cov xim zinc qub yog xim ntsuab-dawb, thiab cov xeb dawb npib tsib xee dawb piv rau cov xim sib txawv ntau dua.

• Dawb Nickel：

Cov txheej txheem plating yog: tshem roj - ntxuav - ua kom tsis muaj zog acid - ntxuav - tooj liab hauv qab - ua kom - ntxuav - electroplating nickel- Ntxuav - passivation - ntxuav - ziab - lossis kaw, thiab cov txheej txheem nickel dub yeej zoo ib yam, feem ntau cov mis tshuaj plating yog txawv, tsawg dua zinc sulfide thiab koom nrog. Nickel yog hlau nyiaj-dawb daj, rau qhov zoo nkauj dua, yuav koom nrog nickel-plated brightener. Nws qhov kev tiv thaiv corrosion thiab nickel dub tsis sib txawv ntau 6-12 teev, cov txheej txheem ntawm cov tuam txhab feem ntau kuj yuav dhau roj lossis kaw, xws li xav txog qhov cuam tshuam ntawm corrosion rau cov khoom yas ntawm cov khoom nkag los yuav tsum siv ua qhov tseem ceeb rau kev tswj seb puas dhau roj lossis tsis dhau roj.

• Xiav zinc, ntsuab zinc：

Cov txheej txheem zoo ib yam li cov zinc dawb, zinc xiav yog cov zinc oxide zaj duab xis uas muaj 0.5-0.6mg/dm2 ntawm trivalent chromium. Kev ua kom ntsuab, tseem hu ua tsib-acid passivation, tuaj yeem tau txais cov zaj duab xis ntsuab tuab, cov kua passivation muaj cov phosphate ions, cov zaj duab xis ntsuab ci ntsa iab yog cov zaj duab xis tiv thaiv uas muaj cov chromates thiab phosphates sib xyaw ua ke.

Vim nws txoj kev tiv taus corrosion, xiav zinc zoo dua li dawb zinc, thaum ntsuab zinc zoo dua li xiav zinc. Xim ntawm xiav zinc yog me ntsis xiav thiab dawb zinc yog ze rau kev lag luam kom siv ntau dua, qhov kawg kuj tseem siv tau ua cov khoom tsim thaum lwm txoj hauv kev ntawm cov ntsia hlau.

• Zinc enamelled (chemistry)：

Hauv pawg galvanizing ntawm cov txheej txheem ntawm cov xim zinc yog qhov zoo tiv thaiv corrosion, nws cov txheej txheem xim passivation yog: galvanizing - ntxuav - 2% - 3% nitric acid tawm ntawm lub teeb - ntxuav - tsawg chromium xim passivation - ntxuav - Ci laus. Qhov kub passivation qis dhau, zaj duab xis qeeb, zaj duab xis daj nyias. Kub siab, zaj duab xis tuab thiab xoob, tsis lo rau. Nws yog qhov zoo tshaj plaws los tswj ntawm kwv yees li 25 degrees kom ntseeg tau tias tib xim tau txais hauv ib lub sijhawm.

Tom qab passivation, nws yuav tsum tau ci thiab laus kom txhim kho qhov adhesion thiab corrosion tsis kam ntawm zaj duab xis. Xim zinc-plated screws los ntawm kev kov hauv qab ntawm qhov tsis kam rau cov tshuaj tsuag ntsev nruab nrab hauv ntau dua 48 teev, kev tswj hwm zoo tuaj yeem ua tau ntau dua 100 teev.

• Dacromet：

Nws yog lub npe luv thiab txhais lus ntawm DACROMET, piv txwv li flaky zinc-based chromium ntsev tiv thaiv txheej, tseem hu ua zinc-aluminium txheej. Cov txheej txheem yooj yim yog: degreasing - degreasing - txheej - preheating - sintering - txias. Cov txheej txheem feem ntau yuav muaj 2-4 zaug los ntawm txheej mus rau txheej txheem txias, vim tias cov ntsia hlau nrog dip txheej xws li kom ua tiav qee qhov tuab yuav tsum tau ua ntau zaus.

Cov qauv yog nyob rau ntawm qhov chaw hlau, coated nrog ib txheej ntawm Dacromet kua (piv txwv li, muaj cov nplai ntawm zinc, txhuas [cov nplai feem ntau loj 0.1-0.2X10-15 microns] Cr03 thiab cov organic tshwj xeeb ntawm cov kua dej sib xyaw ua ke), los ntawm 300 ° C lossis yog li ntawd kev khaws cia cua sov ci ib lub sijhawm, Dacromet kua hauv hexavalent chromium raug txo kom trivalent chromium, ua rau amorphous composite chromate compounds (nCr03) mCr203).

Kev tiv thaiv xeb zoo heev, tsis muaj ntsev txog li 300 teev lossis ntau dua, qhov tsis zoo ntawm cov txheej tsis sib xws, qhov chaw nyias ntawm 5-10um, qhov chaw tuab ntawm 40um lossis li ntawd, nws yuav cuam tshuam rau qhov tob ntawm lub hau ntswj, yog li lub tshuab tapping ntsia hlau thiab cov ntsia hlau nrog lub taub me me ntawm cov ntsia hlau zoo heev uas tsis siv Dacromet txheej txheem ua kev kho saum npoo.