Thaum lub workpiece nrog roj stains yog immersed nyob rau hauv ib qho kev daws nplua nuj nyob rau hauv active tshuaj, lub Ameslikas disordered surfactant molecules muaj hydrophobic pawg taw tes rau cov roj zaj duab xis thiab hydrophilic pawg taw tes rau cov aqueous tov. Lawv tau teem caij kom zoo rau ntawm qhov chaw ntawm lub workpiece, thiab txhua pab pawg muaj nws lub suab. Nyob rau hauv txoj kev no, thawj adsorption ntawm ob lub interfaces ua rau txo qis ntawm qhov nro ntawm lub moos kho kom zoo nkauj. Nyob rau hauv lub convection thiab mixing nyhuv ntawm cov roj kub tshem tawm cov kua, cov roj zaj duab xis yog thawb los tsim kua muag, tsim cov roj tee dej uas poob los ntawm qhov chaw ntawm lub workpiece thiab maj mam tsim zoo heev me me pob. Nyob rau saum npoo ntawm cov pob me me, cov neeg ua haujlwm saum npoo av yog adsorbed, nrog cov pab pawg hydrophilic ntsib sab nraud thiab cov pab pawg hydrophobic ntsib sab hauv. Yog li ntawd, sib tov ntawm ob immiscible kua ua emulsion. Cov roj tee maj mam nce thiab sib sau rau ntawm qhov chaw ntawm cov roj tshem tawm los tsim cov roj txheej, uas yog tom qab ntawd tshem tawm. Tshuaj degreasing yog txheeb ze rau hluav taws xob degreasing. Nws siv cov nyhuv saponification ntawm cov tshuaj kub alkali kom tshem tawm cov roj saponified, thiab cov nyhuv emulsification kom tshem tawm cov roj uas tsis yog saponified. Cov tshuaj tiv thaiv ntawm saponification yog cov nyhuv alkaline ntawm cov tsiaj thiab zaub roj nrog sodium hydroxide los tsim dej -soluble xab npum thiab glycerol. Qhov no yog ib txoj hauv kev tshem cov roj los ntawm kev hloov nws mus rau lwm yam khoom los ntawm kev siv tshuaj lom neeg. Cov roj ntxhia yog cov roj uas tsis muaj saponified uas tsis hnov mob nrog alkali, tab sis tuaj yeem tawg los ntawm cov nyhuv emulsification, tawg tawm ntawm qhov chaw ntawm titanium pas nrig kom tshem tawm cov roj.
Los ntawm qhov no, nws tuaj yeem xaus lus tias cov xwm txheej tsim nyog rau kev tshem tawm cov roj chemical yog raws li hauv qab no:
1. nplua nuj nyob rau hauv ob qho tib si alkalis thiab surfactants.
2. Nws muaj micro tov tov (feem ntau rhuab) los yog macro phau ntawv sib tov. Chav tsev kub tshem tawm roj tsuas yog tso siab rau cov nyhuv emulsification ntawm cov neeg ua hauj lwm sab nraud. Thaum sib tov sab nraud tsis siv, cov roj tshem tawm lub hwj chim tsis zoo li cov roj uas muaj cov roj rhuab. Cov tshuaj tiv thaiv ceev ntawm saponification kuj nrawm nrog qhov nce ntawm qhov kub thiab txias. Yog li ntawd, rau chav tsev kub los yog qis- cov neeg ua haujlwm roj kub, nws yog ib qho tsim nyog yuav tsum siv lawv hauv kev tsim khoom loj raws li kev sim me me thiab xav tias lawv ua tau. Thaum npaj cov kab ntau lawm, cov lus nug no yuav tsum tau ua tib zoo xav.
3. Hlau ion impurities yog inevitably nplua nuj nyob rau hauv cov tshuaj degreasing, thiab lawv kuj muaj peev xwm rov qab tau ntawm lub cathode workpiece, ua rau dub los yog daim txhuam cev zoo li cov khoom uas cuam tshuam rau adhesion ntawm txheej.
4. Thaum cov titanium tivthaiv nyob rau hauv lub cathode, cov roj hluav taws xob tshem tawm yog hu ua nto ntawm cathode degreasing titanium pas nrig, thaum cov roj hluav taws xob tshem tawm ntawm lub workpiece ntawm lub anode yog hu ua anode degreasing.
Qhov zoo ntawm cathodic roj tshem tawm:
A. Electrolysis ntawm 1 mole ntawm dej tuaj yeem tsim 1 mole ntawm hydrogen, thaum electrolysis ntawm 2 moles ntawm dej tuaj yeem tsim tau 1 mole ntawm oxygen. Thaum raug rau tib tus nqi hluav taws xob, qhov ntim ntawm cov roj tsim tawm ntawm lub cathode yog ob npaug ntawm cov roj uas tsim tawm ntawm lub anode. Qhov tshwm sim ntawm cov pa roj yog qhov laj thawj tseem ceeb vim li cas hluav taws xob tshem tawm cov roj.
B. Yeej tsis corrode lub workpiece. Cov hydrogen generated ntawm lub cathode muaj cov nyhuv rov qab, uas tsis oxidize cov hlau atoms ntawm qhov chaw ntawm lub workpiece, thiab nws tsis poob electrons thiab yaj los ntawm lub workpiece nyob rau hauv ib tug ionic xeev. Yog li ntawd, tooj liab thiab tooj liab alloys, nrog rau zinc thiab zinc alloys (xws li tuag-castings), tsuas yog degreased siv cathode. Txwv tsis pub, qhov saum npoo yuav oxidize thiab tig dub, los yog raug kev txom nyem los ntawm corrosion hnyav.
