Dahaarka Chromate ee dusha aluminium

Aluminiumka iyo aluminiumyada aluminiumka waxaa lagu daaweeyaa dahaar beddelaad u adkaysta oo loo yaqaan "daahan chromate" ama "chromating". General Habka waa in la nadiifiyo oogada aluminium ka dibna lagu dabaqo ka kooban chromium acidic dushaas nadiif ah. Dahaarka beddelka Chromium ayaa ah kuwo si heersare ah u adkaysta daxalka waxayna bixiyaan sii hayn heersare ah oo dahaarka xiga ah. Noocyo kala duwan oo ka mid ah dahaarka xiga ayaa lagu dabaqi karaa dahaarka beddelka chromate si loo soo saaro dusha la aqbali karo.

Waxa aan ugu yeerno fosfatinta ilaa birta birta waxaa loo yaqaan chromating ee dusha aluminium. Waxa kale oo loo yaqaan sida daahan alodine. Waxaa jira noocyo chromating jaale ah, cagaar iyo hufan. Koorasyada jaalaha ah ee koromamada Cr+6, jaakadaha koroomada cagaaran ee Cr+3. Miisaanka daboolku wuu kala duwanaan karaa iyadoo loo eegayo wakhtiga codsiga iyo nooca dahaarka. Heerkulka qallajinta waa inuusan dhaafin 65 º C ee chromate jaalaha ah iyo 85 º C daahanada koomaytada cagaaran iyo kuwa hufan.

Waa muhiim in la bixiyo nadiif, oogada dufanka ka hor inta aan la isticmaalin chromate. Haddi la diyaariyo qubeyska kululaynta, qubeyska caustic iyo dabaasha qubayska nitric acid ayaa loo isticmaali karaa wax lagu guro. Dhanka kale, qubayska aashitada ah ayaa leh awood wax-ku-ool ah lafteeda. Ku-dhejinta rinjiga iyo ku-dhejinta rinjiga waxay aad ugu fiicnaan doontaa dusha aluminium ee la soo qaaday iyo kuwa xaalufiyey.

Oo ay la socdaan bixinta caabbinta daxalka sare iyo guryaha adhesion rinjiga dusha aluminium, waxaa si fiican loo og yahay in rabitaanka muuqaalka laga yaabaa in la hagaajiyo by samaynta daahan chromate ah iyada oo la xidhiidha dusha oo leh xal daahan beddelka aqueous ka kooban ion chromium iyo daro kale.