Kev kho deg txheej txheem ntawm cov khoom yas ua ntej plating

Kev kho saum npoo ntawm cov khoom yas feem ntau suav nrog kev kho cov txheej txheem thiab cov txheej txheem plating.

Feem ntau, cov crystallinity ntawm plastics yog loj, polarity yog me me los yog tsis yog -polar, thiab lub zog saum npoo yog tsawg, uas cuam tshuam rau adhesion ntawm txheej. Txij li cov yas yog ib qho tsis yog - conductive insulator, nws tsis tuaj yeem plated ncaj qha rau ntawm cov yas raws li cov txheej txheem plating. Yog li ntawd, ua ntej kev kho deg, qhov tsim nyog pretreatment yuav tsum tau ua los txhim kho lub zog sib txuas ntawm txheej thiab muab cov khoom siv hluav taws xob nrog lub zog sib txuas zoo rau plating.


Ua ntej-kev kho rau txheej

Cov kev kho ua ntej - suav nrog kev kho degreasing ntawm cov yas nto, piv txwv li ntxuav cov roj saum npoo thiab tso tawm tus neeg sawv cev, thiab ua kom muaj kev kho mob ntawm cov yas saum npoo, txhawm rau txhim kho cov adhesion ntawm cov txheej uas tau coated.


1. Degreasing ntawm cov khoom yas


Zoo ib yam li cov khoom siv hlau nto degreasing, cov khoom yas degreasing tuaj yeem ntxuav nrog cov kuab tshuaj organic lossis cov tshuaj alkaline aqueous uas muaj surfactants tshem tawm cov roj. Organic kuab tshuaj degreasing yog tsim rau tu paraffin, beeswax, rog, thiab lwm yam organic av los ntawm cov yas nto, cov organic solvent siv yuav tsum insoluble, tsis yog - o, tsis yog - yas cracking, nws tus kheej tsawg. boiling point, yooj yim rau evaporate, tsis yog - lom, thiab tsis yog -flammable.


Cov tshuaj alkaline aqueous yog tsim rau degreasing ntawm alkali -cov yas resistant. Cov tshuaj muaj caustic soda, alkaline ntsev, thiab ntau yam saum npoo-cov tshuaj nquag. Qhov feem ntau siv deg- cov khoom nquag yog OP series, piv txwv li alkylphenol polyoxyethylene ether, uas tsis tsim ua npuas ncauj thiab tsis nyob hauv cov yas.


2. Ua kom lub ntsej muag ntawm cov khoom yas


Qhov kev ua kom zoo no yog txhawm rau txhim kho lub zog saum npoo ntawm cov yas, uas yog, tsim kom muaj qee pawg polar nyob rau saum npoo ntawm cov yas los yog roughen nws, thiaj li ua rau cov txheej txheej yooj yim rau ntub thiab adsorb rau ntawm qhov chaw. Muaj ntau txoj hauv kev ua kom ntog, xws li tshuaj oxidation, nplaim oxidation, hnyav vapor etching thiab corona tawm oxidation.

Feem ntau siv yog cov tshuaj siv lead ua oxidation kev kho mob, txoj kev no feem ntau yog siv rau hauv cov tshuaj chromic acid kho, nws cov mis raug yog 4.5 feem pua ​​​​poov tshuaj dichromate, 8.0 feem pua ​​dej, concentrated sulfuric acid (ntau tshaj 96 feem pua. 87.5 feem pua.


Qee cov khoom yas, xws li polystyrene thiab ABS yas, kuj tuaj yeem coated ncaj qha yam tsis muaj tshuaj oxidation kho.

Txhawm rau kom tau txais qib siab - txheej txheej zoo, tshuaj oxidation kev kho mob kuj tseem siv, xws li ABS yas tom qab degreasing, uas tuaj yeem siv ntau dua dilute chromic acid kho etching, cov qauv kev kho mob yog chromic acid 420g / L. , sulfuric acid (qhov tshwj xeeb lub ntiajteb txawj nqus 1.83) 200ml / L. Cov txheej txheem kev kho mob yog 65 degree 70 degree / 5min10min, dej ntxuav, ziab.


Qhov zoo ntawm etching nrog chromic acid kev daws teeb meem yog tias cov khoom siv yas tuaj yeem kho tau tusyees txawm tias qhov nyuaj ntawm cov khoom zoo li cas, thiab qhov tsis zoo yog tias kev ua haujlwm yog qhov txaus ntshai thiab muaj teeb meem ua paug.

Ua ntej-kev kho rau txheej


Lub hom phiaj ntawm pretreatment yog los txhim kho cov adhesion ntawm plating rau cov yas nto thiab tsim ib tug conductive hlau puag txheej ntawm cov yas nto.

Cov txheej txheem ua ntej - kho muaj xws li: mechanical roughening, chemical degreasing, chemical roughening, rensitization, activation, reduction, and chemical plating. Thawj peb ntawm lawv yog los txhim kho cov adhesion ntawm plating txheej, thiab plaub kawg yog los tsim cov hlau conductive txheej txheej.


1. Mechanical roughening thiab chemical roughening


Mechanical roughening thiab tshuaj roughening kev kho mob yog siv los coarsen nto ntawm cov yas los ntawm txhua yam thiab tshuaj txoj kev, thiaj li yuav ua rau kom qhov chaw sib cuag ntawm lub plating thiab lub substrate. Nws feem ntau ntseeg tias lub zog sib txuas ua tiav los ntawm kev siv tshuab roughening tsuas yog kwv yees li 10 feem pua ​​​​ntawm cov tshuaj roughening.


2. Tshuaj degreasing


Txoj kev tshem cov roj ua ntej txheej txheej yas yog tib yam li tshem cov roj ua ntej txheej.


3. Kev xav


Sensitization yog ua kom muaj peev xwm adsorption ntawm cov yas nto adsorption ntawm qee yam yooj yim rau oxidize tshuaj, xws li tin dichloride, titanium trichloride, thiab lwm yam. activation kev kho mob, thiab tus activator yog txo mus rau catalytic nuclei, uas nyob twj ywm rau saum npoo ntawm cov khoom. Lub luag hauj lwm ntawm rhiab heev yog los nteg lub hauv paus rau cov tshuaj txheej tom ntej ntawm cov hlau txheej.


4. Kev ua haujlwm


Kev ua kom muaj zog yog kev kho mob ntawm qhov chaw sensitized nrog kev pab los ntawm kev daws ntawm catalytically active hlau tebchaw. Nyob rau hauv qhov tseeb, cov khoom nrog ib tug adsorbed txo tus neeg sawv cev yog immersed nyob rau hauv ib tug aqueous tov ntawm oxidizing tus neeg saib xyuas uas muaj precious hlau ntsev, whereupon lub precious hlau ions raug txo los ntawm S2 ntxiv rau n raws li ib tug oxidizing tus neeg saib xyuas, thiab txo nqi precious hlau yog deposited li colloidal hais. nyob rau saum npoo ntawm cov khoom, uas muaj zog catalytic kev ua si. Thaum xws li ib tug nto yog immersed nyob rau hauv cov tshuaj plating tov, cov hais los ua lub catalytic chaw, ua rau cov tshuaj tiv thaiv ceev ntawm tshuaj plating sai.


5. Txo kev kho mob

Tom qab ua kom tiav thiab ntxuav nrog dej, ua ntej chemical plating, cov khoom yog impregnated nrog ib tug tej yam concentration ntawm cov tshuaj txo tus neeg sawv cev siv nyob rau hauv chemical plating thiaj li yuav tshem tawm cov unwashed activator txo, uas yog hu ua txo kev kho mob. Nyob rau hauv cov ntaub ntawv ntawm chemical tooj liab plating, formaldehyde tov yog siv los txo cov kev kho mob, thiab nyob rau hauv cov ntaub ntawv ntawm chemical nickel plating, sodium hypophosphite tov yog siv los txo cov kev kho mob.

6. Tshuaj plating


Lub hom phiaj ntawm cov tshuaj plating yog tsim cov yeeb yaj kiab hlau rau ntawm cov khoom yas los tsim cov txheej txheem rau plating hlau txheej ntawm cov khoom yas, yog li cov tshuaj plating yog cov kauj ruam tseem ceeb ntawm cov yas plating.