Pretreatment txheej txheem rau aluminium nto kho

Aluminium yog tsis ruaj tsis khov nyob rau hauv cov huab cua thiab yooj yim tsim ib tug oxide zaj duab xis uas yog ib qho nyuaj rau paub txog ntawm qhov muag liab qab. Vim yog qhov sib txawv ntawm cov casting thiab kev tsim cov txheej txheem ntawm txhuas qhov chaw, uas yog ncaj qha txiav los ntawm extruded nplooj ntawv, los yog tsim los ntawm mechanical precision processing, los yog tsim los ntawm cov txheej txheem sib txawv thiab tom qab ntawd raug rau kev kho cua sov los yog vuam, qhov chaw ntawm lub workpiece yuav tawm txawv. xeev thiab sib txawv ntawm cov av los yog cov cim. Nyob rau hauv txoj kev kho ua ntej, txoj kev kho ua ntej yuav tsum raug xaiv raws li qhov tseeb ntawm qhov chaw ua haujlwm.
Kev saib xyuas yuav tsum tau them rau cov txheej txheem ua ntej kev kho mob ntawm precision machined qhov chaw: Txawm hais tias lub ntuj oxide zaj duab xis nyob rau saum npoo ntawm precision machined qhov chaw tsuas yog pib tsim thiab yooj yim tshem tawm, nws yog ilv thiab hnyav, tshwj xeeb tshaj yog nyob rau hauv thiab ib ncig ntawm lub eyelets ( ntxiv vim lubrication xav tau thaum lub sij hawm machining). Cov hom workpieces no yuav tsum tau ntxuav nrog cov kuab tshuaj organic ua ntej. Yog hais tias ncaj qha ntxuav nrog alkali, tsis tsuas yog nws nyuaj rau tshem tawm cov roj thiab hnyav, tab sis qhov precision machined nto tsis tuaj yeem tiv taus lub sij hawm ntev muaj zog alkali corrosion, qhov tshwm sim kuj yuav cuam tshuam qhov roughness ntawm workpiece nto thiab haum ntawm tolerances, thaum kawg. ua seem.
Nyob rau hauv cov txheej txheem ua ntej ntawm casting molded qhov chaw, kev saib xyuas yuav tsum tau them rau cov teeb meem hauv qab no: tsis yog txhua qhov chaw ntawm casting molded qhov chaw tau dhau los ua cov txheej txheem ua haujlwm, thiab qhov chaw uas tsis tau raug machined muaj cov txheej txheem oxide tuab heev tsim thaum lub sij hawm ua haujlwm. txheej txheem casting, qee qhov kuj yog sandwiched nrog cov xuab zeb txheej. Feem ntau, cov txheej txheem machining lossis sandblasting ua ntej tshem tawm cov oxide zaj duab xis hauv cheeb tsam no, lossis ntxuav alkali ua ntej ua haujlwm. Tsuas yog nyob rau hauv txoj kev no tuaj yeem ua cov txheej txheem oxide qub hauv thaj chaw tsis ua haujlwm raug tshem tawm tag nrho, Thiab zam kev hloov pauv ntawm qhov ntev ntawm cov khoom siv machined.
Thaum lub sij hawm ua ntej kev kho mob ntawm workpieces uas tau kho cua sov los yog vuam, yuav tsum tau them nyiaj mloog mus rau cov nram qab no cov teeb meem: raws li tus txheej txheem yuav tsum tau, lub workpieces yuav tsum tau ntxuav nrog organic solvents ua ntej yuav raug xa mus rau lub tshav kub kho los yog vuam txheej txheem. kom tshem tawm cov roj stains. Txawm li cas los xij, tam sim no, qhov no feem ntau tsis tuaj yeem ua tau. Yog li ntawd, ib txheej ntawm oily thiab sintered coke yog tsim nyob rau saum npoo ntawm lub workpieces, uas yog ib qho nyuaj rau tshem tawm nyob rau hauv cov organic solvents. Yog hais tias soaked nyob rau hauv alkaline tov, nws yuav ua rau lub zos corrosion, tsim pitting los yog unevenness, heev cuam tshuam cov khoom zoo. Soak cov txheej txheem coking no hauv cov concentrated nitric acid kom nws soften. Tom qab cov khoom siv coking softened, nws tuaj yeem raug tshem tawm tag nrho los ntawm kev ntxuav me ntsis hauv cov tshuaj alkaline.