Taw qhia: Cov txheej txheem tsim khoom ntawmcov khoom yasFeem ntau suav nrog plaub txheej txheem tseem ceeb: pwm tsim, kho saum npoo, luam ntawv, thiab sib dhos. Kev kho qhov saum npoo yog qhov tseem ceeb ntawm qhov tsis tseem ceeb. Txhawm rau txhim kho kev sib raug zoo ntawm cov txheej txheem thiab muab lub hauv paus zoo rau cov plating, cov txheej txheem ua ntej kho yog qhov tseem ceeb.
Nto pretreatment ntawm cov khoom yas
Feem ntau suav nrog txheej txheej thiab kev kho plating. Feem ntau, cov yas muaj qhov loj ntawm crystallinity, me polarity los yog tsis muaj polarity, thiab tsis tshua muaj zog nto, uas yuav cuam tshuam rau adhesion ntawm txheej. Txij li cov yas yog cov khoom siv hluav taws xob tsis zoo, nws tsis tuaj yeem raug plated ncaj qha rau ntawm cov yas raws li cov txheej txheem electroplating dav dav. Yog li ntawd, ua ntej kev kho deg, qhov tsim nyog pretreatment yuav tsum tau nqa tawm los txhim kho lub zog ntawm kev sib txuas ntawm txheej thiab muab cov txheej txheem hauv qab uas muaj kev sib txuas zoo rau lub plating.
Pretreatment ntawm txheej
Pretreatment suav nrog degreasing ntawm yas nto, piv txwv li ntxuav cov roj thiab tso tawm tus neeg sawv cev ntawm qhov chaw, thiab ua kom lub ntsej muag yas, txhawm rau txhim kho cov adhesion ntawm txheej.
1. Degreasing
Degreasing ntawmcov khoom yas. Zoo ib yam li degreasing ntawm cov khoom hlau, degreasing ntawm cov khoom yas tuaj yeem ua los ntawm kev ntxuav nrog cov kuab tshuaj organic lossis degreasing nrog alkaline aqueous daws uas muaj surfactants. Degreasing nrog cov kuab tshuaj organic yog tsim los ntxuav cov tshuaj paraffin, beeswax, roj thiab lwm yam organic av los ntawm cov yas nto. Cov kuab tshuaj organic siv yuav tsum tsis txhob yaj, o lossis tawg cov yas, thiab nws muaj qhov kub tsis tshua muaj kub, tsis muaj kuab lom, tsis muaj tshuaj lom thiab tsis tawg. Alkaline aqueous daws yog tsim rau degreasing alkali-resistant plastics. Cov tshuaj muaj caustic soda, alkaline ntsev thiab ntau yam surfactants. Feem ntau siv surfactant yog OP series, piv txwv li alkylphenol polyoxyethylene ether, uas tsis tsim ua npuas ncauj thiab tsis nyob rau hauv cov yas nto.
2, Nto ua kom tiav
Qhov kev ua kom zoo no yog txhawm rau txhim kho cov khoom nto ntawm cov yas, uas yog, tsim qee pawg polar ntawm cov yas saum npoo los yog roughen nws kom cov txheej tuaj yeem yooj yim dua wetted thiab adsorbed rau ntawm qhov chaw ua haujlwm. Muaj ntau txoj hauv kev rau kev kho qhov chaw ua haujlwm, xws li tshuaj oxidation, nplaim oxidation, hnyav vapor etching thiab corona tawm oxidation. Qhov siv ntau tshaj plaws yog tshuaj siv lead ua oxidation kev kho mob, uas feem ntau siv chromic acid kho kua, thiab nws cov mis raug yog 4.5% potassium dichromate, 8.0% dej, thiab 87.5% sulfuric acid (ntau tshaj 96%).
Qee cov khoom yas, xws li polystyrene thiab ABS yas, tuaj yeem coated ncaj qha yam tsis muaj tshuaj oxidation kho. Txhawm rau kom tau txais cov txheej txheem zoo, kev kho tshuaj oxidation kuj tseem siv. Piv txwv li, tom qab degreasing, ABS yas yuav etched nrog ib tug dilute chromic acid kho kua. Nws cov qauv kev kho mob raug yog 420g / L chromic acid thiab 200ml / L sulfuric acid (qhov tshwj xeeb lub ntiajteb txawj nqus 1.83). Cov txheej txheem kev kho mob raug yog 65 ℃ 70 ℃ / 5min 10min, ntxuav dej, thiab ziab. Qhov kom zoo dua ntawm etching nrog chromic acid kho kua yog tias txawm li cas los xij cov duab ntawm cov khoom yas yog qhov nyuaj, nws tuaj yeem kho tusyees. Qhov tsis zoo yog tias kev ua haujlwm yog qhov txaus ntshai thiab muaj teeb meem ua paug.
Pretreatment ntawm txheej txheej
Lub hom phiaj ntawm pretreatment ntawm txheej txheej yog los txhim kho cov adhesion ntawm txheej rau cov yas nto thiab tsim ib tug conductive hlau hauv qab txheej ntawm cov yas nto. Cov txheej txheem pretreatment feem ntau suav nrog: mechanical roughening, chemical degreasing, chemical roughening, sensitization treatment, activation treatment, reduction treatment and chemical plating. Thawj peb yam khoom yog los txhim kho qhov adhesion ntawm txheej, thiab plaub yam khoom kawg yog los tsim cov txheej txheem hlau hauv qab.
1, Mechanical roughening thiab tshuaj roughening
Mechanical roughening thiab chemical roughening kev kho mob yog ua kom cov yas nto rougher los ntawm kev siv tshuab thiab cov txheej txheem tshuaj raws li kom muaj kev sib cuag ntawm cov txheej thiab substrate. Nws feem ntau ntseeg tau tias lub zog sib txuas uas tuaj yeem ua tiav los ntawm kev siv tshuab roughening tsuas yog kwv yees li 10% ntawm cov tshuaj roughening.
2. Tshuaj degreasing
Txoj kev degreasing rau pretreatment ntawm yas nto txheej yog tib yam li txoj kev degreasing rau pretreatment ntawm txheej.
3. Kev xav
Sensitization yog adsorb qee yam yooj yim oxidized, xws li tin dichloride, titanium trichloride, thiab lwm yam, nyob rau saum npoo ntawm plastics nrog qee qhov muaj peev xwm adsorption. Cov adsorbed yooj yim oxidized tshuaj yog oxidized thaum ua kom kho, thiab tus activator txo mus rau catalytic crystal nuclei thiab tseem nyob rau saum npoo ntawm cov khoom. Lub luag hauj lwm ntawm rhiab heev yog los nteg lub hauv paus rau cov tshuaj tom ntej plating hlau txheej.
4 、 Ua kom tiav
Kev ua kom muaj zog yog kho qhov chaw sensitized nrog kev pab los ntawm kev daws ntawm catalytically active hlau tebchaw. Nws cov ntsiab lus yog raus rau hauv cov khoom adsorbed nrog tus neeg sawv cev txo qis hauv cov tshuaj aqueous uas muaj cov oxidant ntawm cov hlau muaj nuj nqis ntsev, kom cov hlau muaj nuj nqis ions raug txo los ntawm S2 + n raws li oxidant, thiab cov hlau muaj nuj nqis txo tau tso rau hauv nto ntawm cov khoom nyob rau hauv daim ntawv ntawm colloidal hais, uas muaj ib tug muaj zog catalytic kev ua si. Thaum qhov chaw no yog raus rau hauv cov tshuaj plating tov, cov khoom no ua catalytic chaw, uas accelerates cov tshuaj tiv thaiv tus nqi ntawm cov tshuaj plating.
5 、 Kev kho txo qis
Ua ntej chemical plating, cov khoom uas tau qhib thiab ntxuav nrog dej huv yog immersed nyob rau hauv ib tug tej yam concentration ntawm txo tus neeg sawv cev tov siv nyob rau hauv chemical plating kom txo thiab tshem tawm cov unwashed activator. Qhov no hu ua kev kho kom txo qis. Thaum cov tshuaj tooj liab plated, cov tshuaj formaldehyde yog siv los txo kev kho mob, thiab thaum cov tshuaj npib tsib xee plated, sodium hypophosphite tov yog siv los txo 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 electroplating hlau txheej ntawm cov khoom yas. Yog li, tshuaj plating yog ib kauj ruam tseem ceeb hauv cov yas electroplating.
Lub sij hawm xa tuaj: Jun-13-2024