Yuav kom paub thiab tswj tau cov txheej txheem tshem tawm roj zoo, yuav tsum nkag siab txog lub hauv paus ntsiab lus ntawm kev sib txuas ntawm cov txheej thiab cov hlau substrate. Qhov no feem ntau tsis quav ntsej, yog li ua rau muaj teeb meem hauv kev xyaum.
Cov ntaub ntawv cuam tshuam qhia tias qhov kev sib txuas ntawm lub cev uas tshwm sim los ntawm qhov me me ntawm cov txheej thiab qhov chaw ntawm lub substrate tsuas yog muaj zog thaum muaj kev sib txuas ntawm lub zog intermolecular thiab intermetallic ntawm cov txheej thiab cov hlau substrate. Lub zog intermolecular thiab intermetallic tsuas yog tuaj yeem tshwm sim hauv qhov deb me me xwb.
Thaum qhov deb ntawm cov molecule tshaj 5μm, lub zog sib txuas ntawm cov molecular tsis ua haujlwm lawm. Yog li ntawd, ib zaj duab xis roj nyias nyias thiab zaj duab xis oxide ntawm qhov chaw substrate kuj tseem tuaj yeem cuam tshuam lub zog sib txuas ntawm cov molecular lossis cov hlau.
Yuav kom ua tiav qhov kev sib txuas lus saum toj no, nws yog ib qho tsim nyog yuav tsum tshem tawm cov roj av, xeb thiab oxide nplai ntawm cov khoom kom huv si. Lo lus "ua kom huv si" uas peb hais txog tsis tau txhais hais tias qhov chaw yuav tsum huv si tom qab kev kho mob ua ntej plating, tab sis tsuas yog tias nws muaj qhov chaw tsim nyog. Qhov hu ua qhov chaw tsim nyog txhais tau hais tias cov yeeb yaj kiab uas ua rau muaj kev phom sij rau electroplating yuav tsum tau tshem tawm tom qab kev kho mob ua ntej plating thiab hloov los ntawm cov yeeb yaj kiab uas tsim nyog rau kev lees txais electroplating.
Tib lub sijhawm, los ntawm kev kho ua ntej plating, qhov chaw hlau yuav tsum tiaj tiaj. Tom qab kev kho tshuab xws li sib tsoo, polishing, tumbling, sandblasting, thiab lwm yam, cov khawb pom tseeb, burrs thiab lwm yam tsis zoo ntawm qhov chaw raug tshem tawm, yog li qhov chaw substrate ua tau raws li qhov yuav tsum tau ua ntawm substrate leveling thiab ua tiav ntawm cov khoom plated ua ntej tshem tawm roj thiab tshem tawm xeb.
Lub ntsiab lus no yuav tsum meej. Tsuas yog thaum lub ntsiab lus no meej peb thiaj li xaiv tau cov txheej txheem kho ua ntej plating thiab cov mis ntawm cov mis zoo sib xws rau kev kho ua ntej plating.
Yuav ua li cas siv cov txheej txheem degreasing hauv kev tsim khoom?
Feem ntau siv cov tshuaj alkaline degreasing. Cov khoom sib xyaw ntawm cov tshuaj degreasing thiab cov xwm txheej ntawm cov txheej txheem raug xaiv raws li qhov xwm txheej ntawm cov roj pleev thiab hom khoom siv hlau.
Thaum muaj roj ntau lo rau ntawm qhov chaw, uas yog, cov roj txheej tuab heev, muaj roj thiab nplaum, nws tsis yooj yim tshem tawm tsuas yog los ntawm alkaline degreasing. Nws yog qhov tsim nyog siv lwm txoj hauv kev xws li txhuam nrog cov kuab tshuaj rau kev ua ntej degreasing, thiab tom qab ntawd ua alkaline degreasing. Cov kua alkaline degreasing yog alkaline heev, thiab nws yuav ua rau pom tseeb xeb thaum cuam tshuam nrog qee cov hlau.
Yog li ntawd, thaum tshem cov roj pleev rau cov khoom plated xws li txhuas thiab zinc, nws yuav tsum tau ua nyob rau hauv qhov kub qis thiab qis-alkali tej yam kev mob ntau li ntau tau. Nws feem ntau yog siv tau los kho cov khoom hlau nrog alkalinity siab dua, tab sis thaum kho cov khoom tsis yog hlau, pH ntawm cov tshuaj degreasing yuav tsum tau kho kom haum. Piv txwv li, txhuas, zinc thiab lawv cov alloys yuav tsum muaj pH tswj qis dua 11, thiab lub sijhawm tshem cov roj pleev rau cov khoom zoo li no yuav tsum tsis pub tshaj 3 feeb.
Los ntawm qhov pom ntawm tus nqi, qee tus neeg txhawb nqa kev tshem roj hauv qhov kub qis, tab sis kev txo qhov kub tsis sib haum xeeb nrog kev txhim kho kev ua haujlwm. Qhov kub siab dua, qhov ceev ntawm lub cev thiab tshuaj lom neeg ntawm cov roj uas lo rau ntawm qhov chaw thiab cov tshuaj ntxuav sai dua, thiab qhov yooj yim dua rau kev tshem roj.
Kev xyaum tau ua pov thawj tias qhov viscosity ntawm cov roj stains txo qis thaum qhov kub nce siab, yog li degreasing yooj yim dua rau kev ua, tab sis qhov kub qis tsis muaj qhov cuam tshuam no. Yog li ntawd, nws raug txiav txim siab siv cov emulsifiers thiab surfactants. Raws li seb qhov kub siab degreasing zoo thiab qhov kub twg tsim nyog los tswj, tus sau qhov kev paub yog tias 70-80 ° C zoo dua. Qhov no kuj tseem tuaj yeem pab tshem tawm qhov kev ntxhov siab ntawm cov hlau tseem ceeb los ntawm kev siv tshuab, uas yog qhov zoo heev rau kev txhim kho qhov lo rau ntawm txheej, tshwj xeeb tshaj yog ntawm ntau txheej nickels.
Cov khoom siv hlau dav dav tuaj yeem siv cov tshuaj ntxuav ua ke, xws li thawj zaug ntxuav cathodic rau 3-5 feeb, tom qab ntawd ntxuav anodic rau 1-2 feeb, lossis thawj zaug ntxuav anodic rau 3-5 feeb, tom qab ntawd ntxuav cathodic rau 1-2 feeb. Qhov no tuaj yeem ua tiav los ntawm ob txoj kev ntxuav lossis siv lub zog fais fab nrog lub cuab yeej hloov pauv.
Rau cov hlau muaj zog heev, cov hlau caij nplooj ntoos hlav thiab cov khoom nyias nyias, txhawm rau tiv thaiv hydrogen embrittlement, tsuas yog anodic degreasing ua rau ob peb feeb xwb. Txawm li cas los xij, cov khoom tsis yog hlau xws li tooj liab thiab tooj liab alloys tsis tuaj yeem siv anodic degreasing, thiab tsuas yog cathodic degreasing rau 1-2 feeb xwb.
Hais txog kev npaj thiab kev saib xyuas cov tshuaj degreasing, kev npaj cov tshuaj degreasing thiab electrolytic degreasing solutions yog qhov yooj yim heev. Ua ntej, siv 2/3 ntawm lub tank ntim dej los yaj lwm cov khoom tshwj tsis yog surfactants, thiab do tib lub sijhawm (kom tiv thaiv cov tshuaj kom tsis txhob caking). Vim tias cov tshuaj no tso cua sov thaum yaj, tsis tas yuav ua kom sov lawv. Surfactants yuav tsum tau yaj cais nrog dej kub ua ntej ntxiv. Yog tias lawv tsis tuaj yeem yaj ib zaug, cov kua ntshiab sab saud tuaj yeem nchuav tawm thiab tom qab ntawd dej tuaj yeem ntxiv rau kev yaj. Ntxiv rau qhov ntim teev tseg thiab do kom zoo ua ntej siv.
Yuav tsum tau them sai sai rau kev tswj cov kua roj tshem tawm:
① Sim thiab ntxiv cov khoom siv tsis tu ncua. Cov tshuaj surfactants yuav tsum tau ntxiv rau ntawm 1/3 txog 1/2 ntawm cov nyiaj qub txhua lub lim tiam lossis ob lub lim tiam raws li qhov ntau lawm.
② Cov phaj hlau siv yuav tsum tsis txhob muaj cov hlau hnyav ntau dhau kom tiv thaiv lawv kom tsis txhob nkag mus rau hauv cov txheej. Qhov ceev tam sim no yuav tsum tswj hwm ntawm 5-10 A / dm², thiab nws qhov kev xaiv yuav tsum xyuas kom meej tias muaj kev hloov pauv txaus ntawm cov npuas. Qhov no tsis yog tsuas yog xyuas kom meej tias cov roj poob tawm ntawm qhov chaw electrode tab sis kuj ua rau cov tshuaj co. Thaum cov roj ntawm qhov chaw tsis tu ncua, qhov ceev tam sim no ntau dua, qhov ceev ntawm kev tshem tawm roj sai dua.
③ Cov roj av uas ntab hauv lub tank yuav tsum tau muab tshem tawm raws sijhawm.
④ Ntxuav cov av nkos thiab cov av qias neeg hauv lub tank tas li, thiab hloov cov kua dej hauv lub tank sai li sai tau.
⑤ Sim siv cov surfactants uas tsis muaj npuas ntau hauv cov electrolyte; txwv tsis pub, lawv cov kev taw qhia rau hauv lub tank electroplating yuav cuam tshuam rau qhov zoo.
Yuav ua li cas los tswj thiab tswj cov txheej txheem acid etching (pickling)?
Ib yam li cov txheej txheem degreasing, acid etching (pickling) ua lub luag haujlwm tseem ceeb hauv kev kho ua ntej plating. Ob txoj kev no siv ua ke hauv kev tsim ua ntej plating, thiab lawv lub hom phiaj tseem ceeb yog tshem tawm xeb thiab oxide nplai ntawm cov khoom plating hlau.
Feem ntau, cov txheej txheem siv los tshem tawm ntau cov oxides hu ua etching muaj zog, thiab cov txheej txheem siv los tshem tawm cov yeeb yaj kiab oxide nyias uas tsis pom tseeb rau lub qhov muag liab qab hu ua etching tsis muaj zog, uas tuaj yeem faib ua cov tshuaj etching thiab electrochemical etching. Weak etching yog siv ua cov txheej txheem kho mob kawg tom qab etching muaj zog, piv txwv li, ua ntej lub workpiece nkag mus rau hauv cov txheej txheem electroplating. Nws yog ib qho txheej txheem ntawm kev ua kom lub ntsej muag hlau thiab yooj yim tsis quav ntsej hauv kev tsim khoom, uas yog ib qho ntawm cov laj thawj rau electroplating peeling.
Yog tias cov tshuaj etching tsis muaj zog yog ib qho ntawm cov khoom ntawm cov tshuaj plating tom ntej, lossis yog tias nws qhov kev taw qhia yuav tsis cuam tshuam rau cov tshuaj plating, nws yog qhov zoo dua los muab cov khoom plating qhib rau hauv lub tank plating yam tsis tau ntxuav.
Piv txwv li, nrog rau cov kua qaub dilute activation siv ua ntej nickel plating, kom ntseeg tau tias cov txheej txheem etching du, yuav tsum tau ua kom degreasing ua ntej etching; txwv tsis pub, cov kua qaub thiab cov hlau oxides tsis tuaj yeem sib cuag zoo, thiab cov tshuaj yaj tshuaj yuav nyuaj rau kev ua.
Yog li ntawd, txhawm rau kom paub txog acid etching zoo, nws tseem yog qhov tsim nyog los piav qhia cov ntsiab cai yooj yim no hauv kev xav.
Feem ntau, txhawm rau tshem tawm cov oxide nplai ntawm cov hlau thiab cov hlau, sulfuric acid thiab hydrochloric acid feem ntau yog siv rau acid etching. Txoj kev yooj yim, tab sis hauv kev tsim khoom tiag tiag, nws nyuaj rau ua tiav lub hom phiaj xav tau yog tias tsis tau them sai sai.
Cov txheej txheem xaiv rau cov txheej txheem etching ntawm sulfuric acid feem ntau yog raws li kev paub dhau los los txheeb xyuas los ntawm qhov tsos ntawm cov khoom ua haujlwm tom qab pickling, uas, tom qab tag nrho, tsis tuaj yeem tswj tau ntau. Kev xyaum tau qhia tias cov nyhuv ntawm sulfuric acid pickling hauv kev tshem tawm cov nplai oxide ntawm 40 ° C yog ntau dua li ntawm 20 ° C, tab sis thaum qhov kub nce ntxiv, cov nyhuv tev tawv tsis nce ntxiv.
Tib lub sijhawm, hauv sulfuric acid nrog qhov concentration qis dua 20%, thaum qhov concentration nce ntxiv, qhov ceev ntawm acid etching nce ntxiv, tab sis thaum qhov concentration tshaj 20%, qhov ceev ntawm acid etching txo qis. Vim li no, peb ntseeg tias cov txheej txheem txheem ntawm 10% -20% sulfuric acid concentration thiab etching qis dua 60 ° C yog qhov tsim nyog dua. Nws kuj tseem yuav tsum tau sau tseg tias txog qib kev laus ntawm cov kua sulfuric acid, feem ntau, thaum cov ntsiab lus hlau hauv cov kua pickling tshaj 80 g / L thiab cov ntsiab lus ferrous sulfate tshaj 2.5 g / L, cov kua sulfuric acid tsis tuaj yeem siv tau lawm.
Lub sijhawm no, cov tshuaj yuav tsum tau txias kom crystallize thiab tshem tawm cov ferrous sulfate ntau dhau, thiab tom qab ntawd yuav tsum ntxiv cov kua qaub tshiab kom ua tau raws li cov txheej txheem xav tau.
Cov txheej txheem xaiv rau cov txheej txheem acid etching ntawm hydrochloric acid: qhov concentration feem ntau yuav tsum tswj tau ntawm 10% -20%, thiab cov txheej txheem yuav tsum tau ua tiav ntawm chav tsev kub. Piv nrog sulfuric acid, nyob rau hauv tib qho xwm txheej ntawm concentration thiab kub, qhov ceev etching ntawm hydrochloric acid yog 1.5-2 npaug sai dua li ntawm sulfuric acid.
Seb puas siv sulfuric acid lossis hydrochloric acid rau acid etching nyob ntawm qhov xwm txheej tshwj xeeb ntawm kev tsim khoom tiag tiag. Piv txwv li, hauv kev etching muaj zog ntawm cov hlau ferrous, sulfuric acid lossis hydrochloric acid feem ntau siv, lossis "sib xyaw acid" ntawm ob qho tib si hauv ib qho kev faib ua feem.
Txawm li cas los xij, hom kua qaub siv rau kev siv tshuaj lom neeg etching nyob ntawm seb muaj pes tsawg yam thiab cov qauv ntawm cov oxides ntawm qhov chaw ntawm cov hlau thiab hlau. Tib lub sijhawm, nws yog qhov tsim nyog los xyuas kom meej tias qhov ceev etching ceev, tus nqi tsim khoom qis, thiab qhov me me ntawm qhov ntev thiab hydrogen embrittlement ntawm cov khoom hlau li sai tau. Txawm li cas los xij, nws yuav tsum nkag siab tias kev tshem tawm cov nplai oxide hauv hydrochloric acid feem ntau yog nyob ntawm kev yaj tshuaj ntawm hydrochloric acid, thiab cov nyhuv ntawm cov khoom siv ntawm hydrogen yog me dua li ntawm sulfuric acid. Yog li ntawd, kev siv kua qaub thaum siv hydrochloric acid ib leeg yog siab dua li thaum siv sulfuric acid ib leeg.
Thaum cov xeb thiab oxide nplai ntawm qhov chaw ntawm cov khoom plating muaj ntau cov hlau oxides siab, kev sib xyaw acid etching tuaj yeem siv, uas tsis yog tsuas yog ua rau cov hydrogen rhuav tshem ntawm cov nplai oxide xwb tab sis kuj ua rau cov tshuaj yaj ntawm cov oxides sai dua. Txawm li cas los xij, yog tias qhov chaw hlau tsuas muaj cov khoom xeb xoob (feem ntau yog Fe₂O₃), hydrochloric acid ib leeg tuaj yeem siv rau etching vim nws qhov ceev etching, tsawg dua kev yaj ntawm cov substrate, thiab tsawg dua hydrogen embrittlement.
Tab sis thaum cov hlau nto muaj cov nplai oxide ntom ntom, siv hydrochloric acid ib leeg siv ntau dua, muaj tus nqi siab dua, thiab muaj qhov cuam tshuam tsis zoo rau cov nplai oxide dua li sulfuric acid, yog li sulfuric acid zoo dua.
Kev siv hluav taws xob electrolytic etching (electrolytic acid, electrochemical etching), txawm tias yog cathodic electrolysis, anodic electrolysis, lossis PR electrolysis (periodic reversal electrolysis, uas hloov pauv cov ncej zoo thiab tsis zoo ntawm cov khoom ua haujlwm tas li), tuaj yeem ua tiav hauv 5% -20% sulfuric acid kua.
Piv nrog rau kev siv tshuaj lom neeg etching, electrolytic etching tuaj yeem tshem tawm cov nplai oxide uas ruaj khov sai dua, ua rau muaj kev xeb tsawg dua rau cov hlau hauv paus, yooj yim rau kev khiav lag luam thiab tswj hwm, thiab tsim nyog rau cov kab electroplating tsis siv neeg. PR electrolysis yog siv dav hauv Nyiv Pooj los tshem tawm cov nplai oxide ntawm cov hlau tsis xeb.
Hauv Suav teb, ntau tus siv cathodic thiab anodic electrolytic pickling ua ke nrog electrolytic degreasing rau kev kho ua ntej plating. Anodic electrolytic acid rau cov hlau ferrous yog qhov tsim nyog rau kev ua cov khoom hlau nrog ntau cov oxide nplai thiab xeb, thiab nws feem ntau tuaj yeem nqa tawm ntawm chav tsev kub. Kev nce qhov kub tuaj yeem ua rau kom ceev ntawm acid etching, tab sis tsis ntau npaum li tshuaj lom neeg acid etching. Kev nce qhov ceev tam sim no tuaj yeem ua kom ceev ntawm acid etching, tab sis yog tias nws siab dhau, cov hlau puag yuav raug passivated.
Lub sijhawm no, cov tshuaj lom neeg thiab electrochemical yaj ntawm cov hlau hauv paus yeej ploj mus, tsuas yog tshuav cov nyhuv ntawm cov pa oxygen ntawm cov nplai oxide. Yog li ntawd, qhov ceev ntawm etching nce me ntsis, uas yuav tsum tau ua kom txawj ntse. Feem ntau, qhov ceev tam sim no ntawm 5-10 A / dm² yog qhov tsim nyog. Rau anodic acid etching, o-xylene thiourea lossis sulfonated woodworking kua nplaum tuaj yeem siv ua cov tshuaj inhibitors, nrog rau qhov ntau npaum li cas ntawm 3-5 g / L; rau cathodic electrolytic acid ntawm ferrous hlau, sulfuric acid kua tuaj yeem siv, lossis cov kua qaub sib xyaw ntawm kwv yees li 5% sulfuric acid thiab 5% hydrochloric acid, ntxiv rau qhov ntau ntawm sodium chloride. Vim tias tsis muaj cov txheej txheem tshuaj lom neeg thiab electrochemical yaj ntawm cov hlau substrate (hlau), kev ntxiv cov tshuaj uas muaj Cl⁻ kom raug tuaj yeem pab txo cov nplai oxide ntawm qhov chaw ntawm cov khoom thiab ua kom nrawm dua qhov ceev ntawm etching. Tib lub sijhawm, formaldehyde lossis urotropine tuaj yeem siv ua cov tshuaj inhibitors.
Hauv ntej, sulfuric acid yog siv dav rau acid etching ntawm hlau, tooj liab, thiab tooj dag. Ntxiv rau qhov saum toj no, sulfuric acid, ua ke nrog chromic acid thiab dichromates, yog siv ua tus neeg sawv cev rau kev tshem tawm oxides thiab smut ntawm txhuas.
Nws siv ua ke nrog hydrofluoric acid lossis nitric acid lossis ob qho tib si los tshem tawm cov nplai oxide ntawm cov hlau tsis xeb. Qhov zoo ntawm hydrochloric acid yog tias nws tuaj yeem ua kom ntau cov hlau zoo ntawm chav tsev kub; ib qho ntawm nws qhov tsis zoo yog tias yuav tsum tau them sai sai rau kev tiv thaiv HCl pa thiab acid mist pollution.
Ntxiv rau, nitric acid thiab phosphoric acid kuj tseem siv rau hauv kev kho mob ua ntej plating. Nitric acid yog ib qho tseem ceeb ntawm ntau cov neeg sawv cev ci ntsa iab. Nws yog sib xyaw nrog hydrofluoric acid rau kev tshem tawm cov nplai oxide kho cua sov ntawm txhuas, stainless hlau, nickel-based thiab hlau-based alloys, titanium, zirconium, thiab qee cov cobalt-based alloys.
Phosphoric acid siv rau kev tshem tawm xeb ntawm cov hlau thiab tseem siv rau hauv cov tshuaj tshwj xeeb rau cov hlau tsis xeb, txhuas, tooj dag, thiab tooj liab. Cov phosphoric acid-nitric acid-acetic acid sib xyaw acid siv rau kev kho ua ntej ntawm cov khoom txhuas ci ntsa iab. Fluoroboric acid tau ua pov thawj tias yog cov tshuaj pickling zoo tshaj plaws rau cov hlau ua los ntawm cov hlau txhuas lossis tooj liab lossis tooj dag nrog cov tin solder.
Tau muaj kev tshaj tawm tias kev tshem tawm cov hlau oxide nplai thiab oxides siv 5% ntawm lub ntiaj teb cov sulfuric acid ntau lawm, 25% ntawm hydrochloric acid, feem ntau ntawm hydrofluoric acid, thiab ntau ntawm nitric acid thiab phosphoric acid.
Yog li ntawd, kev paub siv cov kua qaub no rau kev ua kua qaub yog qhov tseem ceeb hauv kev siv thev naus laus zis ua ntej plating. Txawm li cas los xij, nws tsis nyuaj rau siv lawv, tab sis nws tsis yooj yim siv lawv zoo, txuag lawv, thiab txo kev siv.
Lub sijhawm tshaj tawm: Lub Ib Hlis-29-2026