Galvanizing
Makhalidwe:
Zinc imakhala yokhazikika bwino mumlengalenga wouma ndipo siisintha mtundu mosavuta. M'madzi ndi m'malo onyowa, imagwirizana ndi mpweya kapena carbon dioxide kupanga mafilimu a oxide kapena alkaline zinc carbonate, zomwe zingalepheretse zinc kupitiriza kusungunuka ndikupereka chitetezo.
Zinc imakhudzidwa kwambiri ndi dzimbiri mu ma acid, alkali, ndi sulfides. Gawo la galvanized nthawi zambiri limafunika kuchitidwa opaleshoni ya passivation. Pambuyo pa passivation mu chromic acid kapena chromate solution, filimu ya passivation yopangidwayo siimawonekera mosavuta ku mpweya wonyowa, zomwe zimapangitsa kuti ikhale yotsutsana ndi dzimbiri. Pazigawo za masika, zigawo zopyapyala (makulidwe a khoma <0.5m), ndi zigawo zachitsulo zomwe zimafuna mphamvu yayikulu yamakina, kuchotsedwa kwa haidrojeni kuyenera kuchitika, pomwe zigawo za mkuwa ndi aloyi zamkuwa sizingafunike kuchotsedwa kwa haidrojeni.
Kupaka galvanizing kumakhala kotsika mtengo, kosavuta kukonza, komanso kumakhala ndi zotsatira zabwino. Mphamvu ya zinc ndi yoipa, kotero utoto wa zinc ndi utoto wa anodic wa zitsulo zambiri.
Galvanization imagwiritsidwa ntchito kwambiri mumlengalenga ndi malo ena abwino. Koma si yoyenera kugwiritsidwa ntchito ngati gawo lothandizira kukangana.
Cchophimba cha chrome
Makhalidwe: Za zinthu zomwe zimakumana ndi mlengalenga wa nyanja kapena madzi a m'nyanja, komanso m'madzi otentha opitilira 70℃, cadmium plating ndi yokhazikika, imakhala ndi mphamvu yolimbana ndi dzimbiri, mafuta abwino, ndipo imasungunuka pang'onopang'ono mu hydrochloric acid yosungunuka, koma imasungunuka kwambiri mu nitric acid ndipo siisungunuka mu alkali. Oxyde yake siisungunukanso m'madzi. Cadmium plating ndi yofewa kuposa zinc plating, yokhala ndi hydrogen yochepa komanso yolimba kwambiri.
Komanso, pansi pa zinthu zina zamagetsi, chophimba cha cadmium chomwe chapezeka chimakhala chokongola kwambiri kuposa chophimba cha zinc. Koma mpweya womwe umapangidwa ndi cadmium panthawi yosungunuka ndi woopsa, ndipo mchere wa cadmium wosungunuka nawonso ndi woopsa. Pansi pa zinthu zabwinobwino, cadmium imagwira ntchito ngati chophimba cha cathodic pachitsulo komanso ngati chophimba cha anodic m'mlengalenga wa nyanja ndi kutentha kwambiri.
Amagwiritsidwa ntchito makamaka kuteteza ziwalo ku dzimbiri la mumlengalenga lomwe limayambitsidwa ndi madzi a m'nyanja kapena madzi ena ofanana ndi mchere, komanso nthunzi yamadzi a m'nyanja yokhuta. Zigawo zambiri m'makampani opanga ndege, apamadzi, ndi zamagetsi, akasupe, ndi zigawo za ulusi zimakutidwa ndi cadmium. Ikhoza kupukutidwa, kupakidwa phosphate, ndikugwiritsidwa ntchito ngati maziko a utoto, koma singagwiritsidwe ntchito ngati chiwiya.
Chophimba cha Chromium
makhalidwe:
Chromium ndi yokhazikika kwambiri mumlengalenga wonyowa, alkaline, nitric acid, sulfide, carbonate solutions, ndi organic acids, ndipo imasungunuka mosavuta mu hydrochloric acid ndi hot concentrated sulfuric acid. Pogwiritsa ntchito mphamvu ya direct current, ngati chromium layer imagwira ntchito ngati anode, imasungunuka mosavuta mu caustic soda solution.
Chigawo cha chromium chili ndi mphamvu yolimba, kuuma kwambiri, 800-1000V, kukana kukalamba bwino, kuwala kwamphamvu, komanso kukana kutentha kwambiri. Sichisintha mtundu pansi pa 480℃, imayamba kusungunuka kuposa madigiri 500℃, ndipo amachepetsa kwambiri kuuma pa 700℃Choyipa chake ndichakuti chromium ndi yolimba, yofooka, komanso yotha kusweka, makamaka ikakumana ndi zinthu zosiyanasiyana. Ndipo ili ndi ma porosity.
Chitsulo cha Chromium chimakonda kugwedezeka mumlengalenga, zomwe zimapangitsa kuti pakhale filimu yosuntha ndipo motero imasintha mphamvu ya chromium. Chifukwa chake, chromium imakhala ngati chophimba cha cathodic pa chitsulo.
Sikoyenera kugwiritsa ntchito pulasitiki yolunjika ya chrome ngati choletsa dzimbiri pamwamba pa zitsulo. Kawirikawiri, pulasitiki yopangidwa ndi electro-layer yambiri (monga copper plating)→chophimba cha nickel→chromium plating) imafunika kuti dzimbiri lithe
kupewa ndi kukongoletsa. Pakadali pano imagwiritsidwa ntchito kwambiri pakukweza kukana kwa ziwalo, kukonza miyeso, kuwunikira kwa kuwala, ndi kuunikira kokongoletsa.
Chophimba cha nikeli
makhalidwe:
Nickel imakhala ndi mphamvu yabwino ya mankhwala mumlengalenga komanso yankho la alkaline, siisintha mtundu mosavuta, ndipo imasungunuka kokha kutentha kopitilira 600.° C. Imasungunuka pang'onopang'ono mu sulfuric acid ndi hydrochloric acid, koma imasungunuka mosavuta mu nitric acid yosungunuka. Imasungunuka mosavuta mu nitric acid yosungunuka ndipo motero imakhala ndi kukana dzimbiri.
Kupaka nikeli kumakhala kolimba kwambiri, kosavuta kupukuta, kumawala kwambiri, ndipo kumatha kuwonjezera kukongola. Kuipa kwake ndikuti kumakhala ndi ma porosity. Kuti muthane ndi vutoli, zokutira zachitsulo zokhala ndi zigawo zambiri zingagwiritsidwe ntchito, ndi nikeli ngati gawo lapakati.
Nickel ndi chophimba cha cathodic cha chitsulo ndi chophimba cha anodic cha mkuwa.
Kawirikawiri amagwiritsidwa ntchito kuteteza zokutira zokongoletsera kuti apewe dzimbiri ndikuwonjezera kukongola. Kuphimba kwa nickel pazinthu zamkuwa ndikwabwino kwambiri popewa dzimbiri, koma chifukwa cha kuchuluka kwa nickel, zitsulo zamkuwa nthawi zambiri zimagwiritsidwa ntchito m'malo mwa nickel.
Nthawi yotumizira: Novembala-14-2024
