Daim ntawv thov ntawm Pickling nyob rau hauv kev kho deg ntawm Aluminium Alloys

 

Tshem tawm cov oxide zaj duab xis thiab impurities: Lub ntuj oxide zaj duab xis yuav tsim nyob rau saum npoo ntawm aluminium alloys thaum lub sij hawm ua los yog cia, thiab impurities kuj yuav txuas nrog. Pickling tuaj yeem tshem tawm cov tshuaj no zoo. Piv txwv li, thaum siv dilute sulfuric acid rau pickling, sulfuric acid (₂₄) yuav hnov ​​​​mob nrog txhuas oxide (₂₃) nyob rau saum npoo ntawm aluminium alloy. Kev sib npaug tshuaj yog ₂₃₂₄₂₄₃₂. Los ntawm cov tshuaj tiv thaiv no, cov oxide zaj duab xis ntawm qhov chaw raug tshem tawm, tawm hauv qhov chaw ntawm aluminium alloy nyob rau hauv lub xeev ntshiab, muab lub hauv paus zoo rau kev kho mob tom ntej. Tsis tas li ntawd, pickling kuj tseem tuaj yeem tshem tawm qee qhov sib xyaw ua ke ntawm cov khoom tsis huv ntawm qhov chaw ntawm aluminium alloy, thiab cov impurities no tuaj yeem cuam tshuam qhov zoo thiab kev ua haujlwm ntawm cov yeeb yaj kiab oxide tom ntej.

 

Kev ua kom lub ntsej muag: Qhov saum npoo ntawm aluminium alloy tom qab pickling muaj ntau dua reactivity. Qhov no yog vim hais tias tom qab cov oxide zaj duab xis raug tshem tawm, cov tshiab aluminium atoms raug rau saum npoo thiab muaj feem yuav hnov ​​​​mob nrog lwm yam tshuaj. Piv txwv li, pickling ua ntej anodizing tuaj yeem txhim kho cov tshuaj tiv thaiv kev ua haujlwm ntawm aluminium alloy thaum lub sij hawm cov txheej txheem anodizing, ua rau cov oxide zaj duab xis generated zoo ib yam thiab ntom. Nyob rau tib lub sijhawm, lub tshuab ua kom lub ntsej muag kuj tseem muaj txiaj ntsig zoo rau kev kho tshuaj hloov pauv tom ntej thiab lwm yam txheej txheem, txhim kho cov reactivity ntawm aluminium alloy thiab cov tshuaj kho.

 

Daim ntawv thov ntawm Alkali ntxuav hauv kev kho deg ntawm Aluminium Alloys

 

Tshem tawm cov roj Stains: Qhov saum npoo ntawm aluminium alloys yuav kis tau nrog cov roj stains thaum ua haujlwm (xws li txiav, stamping, thiab lwm yam). Alkali ntxuav yog ib txoj hauv kev zoo rau kev tshem cov roj stains. Feem ntau, sodium hydroxide () tov los yog sodium carbonate (₂₃) tov thiab lwm yam tshuaj ntxuav alkaline. Noj sodium hydroxide ua piv txwv, nws muaj cov tshuaj tiv thaiv saponification nrog roj. Cov glyceride ntawm cov roj fatty acids ntau dua nyob rau hauv cov roj reacts nrog sodium hydroxide los tsim sodium ntau fatty acid (lub ntsiab ntawm xab npum) thiab glycerol. Cov tshuaj tiv thaiv no tuaj yeem decompose cov roj stains rau hauv dej - cov tshuaj soluble, yog li lawv tuaj yeem yooj yim tshem tawm ntawm qhov chaw ntawm aluminium alloy. Piv txwv li, thaum lub sij hawm tsim cov txheej txheem ntawm aluminium alloy qhov rooj thiab qhov rais, tom qab alkali ntxuav, cov roj stains ntawm qhov chaw raug tshem tawm, kom ntseeg tau tias qhov zoo ntawm cov kev kho mob tom ntej.

 

Synergistic Effect of Surface Cleaning thiab Pretreatment: Alkali ntxuav tsis tau tsuas yog tshem tawm cov roj stains xwb tab sis kuj ua lub luag hauj lwm tu ntawm qhov chaw ntawm aluminium alloy. Thaum lub sij hawm alkali - kev tu, qee qhov me me thiab plua plav yuav raug tshem tawm ua ke. Ntxiv mus, qhov saum npoo ntawm aluminium alloy tom qab ntxuav alkali yog alkaline, uas muaj qee yam kev txhawb nqa rau qee cov txheej txheem tshuaj pretreatment tom ntej (xws li tshuaj hloov pauv tshuaj). Piv txwv li, ua ntej chromating kev kho mob, alkaline nto tom qab alkali ntxuav yog qhov zoo rau cov tshuaj tiv thaiv zoo ntawm cov tshuaj chromate nrog rau saum npoo ntawm aluminium alloy, tsim cov chromate hloov dua siab tshiab zaj duab xis nrog zoo dua.

 

 

 

 

 

 

 

 

 

 

Qib

(wt%) Chemical Composition (wt%)

C

Si

Mi

P

S

Cr

Ni

Mo

Cu

Raws li

Sb

Sn

12Cr2Mo1R (H)

Tsawg dua lossis sib npaug rau 0.15

Tsawg dua lossis sib npaug rau 0.15

0.30-0.60

Tsawg dua lossis sib npaug rau 0.010

Tsawg dua lossis sib npaug rau 0.010

2.0-2.5

Tsawg dua lossis sib npaug rau 0.20

0.90-1.10

Tsawg dua lossis sib npaug rau 0.20

Tsawg dua lossis sib npaug rau 0.016

Tsawg dua lossis sib npaug rau 0.003

Tsawg dua lossis sib npaug rau 0.015

 

 

Kev kho mob chromating

 

Tsim Corrosion - Resistant Conversion Zaj duab xis: Chromating kev kho mob yog tsim ib tug chromate conversion zaj duab xis nyob rau saum npoo ntawm txhuas alloys. Cov chromate ions (₄²⁻) hauv cov tshuaj chromate yuav hnov ​​​​mob nrog cov txhuas atoms ntawm qhov chaw ntawm aluminium alloy los tsim cov chromate hloov dua siab tshiab zaj duab xis nrog zoo corrosion kuj. Piv txwv li, cov tshuaj tiv thaiv mis yuav yog ₄²⁻₂₂⁻. Qhov no chromate hloov dua siab tshiab zaj duab xis tuaj yeem tsim teeb meem ntawm qhov chaw ntawm aluminium alloy, zoo tiv thaiv qhov nruab nrab corrosive los ntawm kev tiv tauj aluminium alloy substrate.

 

Lub luag haujlwm pabcuam hauv Oxide Film Formation: Cov yeeb yaj kiab chromating plays lub luag haujlwm hauv kev tiv thaiv cov substrate hauv thawj theem ntawm oxide zaj duab xis tsim thiab yog qhov tsim nyog rau kev loj hlob tsis tu ncua ntawm cov oxide zaj duab xis tom ntej. Nyob rau hauv cov txheej txheem ntawm kev kho deg ntawm aluminium alloys, kev kho mob chromating yog ua ntej, thiab tom qab ntawd cov txheej txheem tsim cov oxide zaj duab xis (xws li anodizing lossis thermal oxidation) yog nqa tawm, uas tuaj yeem ua rau oxide zaj duab xis loj hlob zoo ib yam thiab tag nrho. Piv txwv li, hauv kev kho saum npoo ntawm qee cov khoom siv aluminium alloy nrog cov kev xav tau siab rau kev tiv thaiv corrosion (xws li cov khoom siv hauv aerospace, cov khoom siv tsheb, thiab lwm yam), aluminium alloy tom qab chromating kev kho mob tuaj yeem tsim cov oxide zaj duab xis nrog zoo dua hauv cov txheej txheem oxidation tom ntej. , yog li txhim kho lub neej kev pab cuam thiab kev ntseeg siab ntawm cov khoom.

 

 

 

 

Cim npe nrov: ABS / bv / ccs / dnv / gl / lr / rina steel phaj rau nkoj tsim, Tuam Tshoj abs / bv / ccs / dnv / gl / lr / rina steel phaj rau nkoj tsim khoom, Hoobkas