Galvanizing
Makhalidwe:
Zinc imakhala yokhazikika mumpweya wowuma ndipo siyisintha mtundu mosavuta. M'madera amadzi ndi chinyezi, amachitira ndi mpweya kapena mpweya woipa kuti apange mafilimu a oxide kapena alkaline zinc carbonate, zomwe zingalepheretse zinc kuti isapitirire oxidize ndi kupereka chitetezo.
Zinc imakhudzidwa kwambiri ndi dzimbiri mu ma acid, alkalis, ndi sulfide. The malata wosanjikiza nthawi zambiri amayenera kulandira chithandizo cha passivation. Pambuyo podutsa mu chromic acid kapena yankho la chromate, filimu yopangidwa ndi passivation sichimawululidwa mosavuta ndi mpweya wonyowa, kupititsa patsogolo mphamvu yake yolimbana ndi dzimbiri. Pazigawo za masika, mbali zoonda-mipanda (makoma a khoma <0.5m), ndi zitsulo zomwe zimafuna mphamvu zamakina apamwamba, kuchotsa haidrojeni kuyenera kuchitidwa, pamene mbali zamkuwa ndi zamkuwa sizingafune kuchotsa hydrogen.
Galvanizing imakhala yotsika mtengo, yosavuta kukonza, komanso imakhala yabwino. Kuthekera koyenera kwa zinki kumakhala koyipa, kotero kuti zokutira za zinki ndizopaka zitsulo zambiri.
Galvanization imagwiritsidwa ntchito kwambiri mumlengalenga komanso malo ena abwino. Koma si yoyenera kugwiritsidwa ntchito ngati chigawo cha mikangano.
Cchrome plating
Makhalidwe: Pazigawo zomwe zimakumana ndi mlengalenga wam'nyanja kapena m'madzi am'nyanja, komanso m'madzi otentha opitilira 70.℃, cadmium plating ndi yokhazikika, imakhala ndi mphamvu yolimbana ndi dzimbiri, mafuta abwino, ndipo amasungunuka pang'onopang'ono mu hydrochloric acid, koma amasungunuka kwambiri mu nitric acid ndi osasungunuka mu alkali. Osayidi yake imasungunukanso m'madzi. Kupaka kwa Cadmium ndikofewa kuposa zokutira zinki, komwe kumakhala kocheperako kwa haidrojeni komanso kumamatira mwamphamvu.
Kuphatikiza apo, mumikhalidwe ina ya electrolytic, zokutira za cadmium zomwe zimapezedwa zimakhala zokongola kwambiri kuposa zokutira zinki. Koma mpweya wopangidwa ndi cadmium ukasungunuka ndi wapoizoni, ndipo mchere wosungunuka wa cadmium ulinso wapoizoni. M'mikhalidwe yabwinobwino, cadmium imakhala ngati zokutira za cathodic pazitsulo komanso ngati zokutira za anodic mumlengalenga wam'nyanja komanso kutentha kwambiri.
Amagwiritsidwa ntchito makamaka kuteteza mbali ku dzimbiri zam'mlengalenga zomwe zimachitika chifukwa cha madzi a m'nyanja kapena njira zofananira zamchere, komanso nthunzi yodzaza m'madzi am'nyanja. Mbali zambiri zamafakitale oyendetsa ndege, apanyanja, ndi zamagetsi, akasupe, ndi zida za ulusi zimakutidwa ndi cadmium. Itha kupukutidwa, phosphated, ndikugwiritsidwa ntchito ngati maziko a penti, koma sangagwiritsidwe ntchito ngati chiwiya.
Chromium plating
makhalidwe:
Chromium imakhala yokhazikika mumlengalenga, alkaline, nitric acid, sulfide, carbonate solutions, ndi organic acids, ndipo imasungunuka mosavuta mu hydrochloric acid ndi otentha kwambiri sulfuric acid. Pansi pa zochita za panopa, ngati chromium wosanjikiza akutumikira monga anode, izo mosavuta sungunuka mu caustic soda solution.
Chosanjikiza cha chromium chimakhala ndi zomatira zolimba, kuuma kwakukulu, 800-1000V, kukana kuvala bwino, kuwunikira kolimba, komanso kukana kutentha kwakukulu. Sisintha mtundu pansi pa 480℃, imayamba kukhala oxidize pamwamba pa 500℃, ndipo amachepetsa kwambiri kuuma pa 700℃. Kuipa kwake ndikuti chromium ndi yolimba, yofewa, komanso imakonda kutsekeka, makamaka ikakumana ndi katundu wosiyanasiyana. Ndipo ili ndi porosity.
Chitsulo cha chromium chimakonda kukhala ndi mpweya, zomwe zimapangitsa kuti pakhale filimu ya passivation ndipo motero kusintha mphamvu ya chromium. Chifukwa chake, chromium imakhala zokutira kwa cathodic pachitsulo.
Sikoyenera kugwiritsa ntchito plating ya chrome ngati anti-corrosion wosanjikiza pamwamba pazitsulo zachitsulo. Nthawi zambiri, multilayer electroplating (ie copper plating→nickel plating→chromium plating) imafunika kukwaniritsa cholinga cha dzimbiri
kupewa ndi kukongoletsa. Pakali pano amagwiritsidwa ntchito kwambiri popititsa patsogolo kukana kwa magawo, kukonzanso miyeso, kunyezimira kowala, ndi kuyatsa kokongoletsa.
Nickel plating
makhalidwe:
Nickel imakhala ndi kukhazikika kwamankhwala mumlengalenga ndi njira ya alkaline, simasinthika mosavuta, ndipo imangokhala ndi okosijeni pamatenthedwe opitilira 600.° C. Imasungunuka pang'onopang'ono mu sulfuric acid ndi hydrochloric acid, koma imasungunuka mosavuta mu nitric acid. Iwo mosavuta passivated mu anaikira nitric asidi choncho ali zabwino dzimbiri kukana.
Nickel plating imakhala yolimba kwambiri, ndiyosavuta kupukutira, imakhala ndi kuwala kwakukulu, ndipo imatha kuwonjezera kukongola. Choyipa chake ndi chakuti ali ndi porosity. Pofuna kuthana ndi vutoli, zokutira zazitsulo zamitundu yambiri zitha kugwiritsidwa ntchito, ndi faifi tambala ngati gawo lapakati.
Nickel ndi zokutira cathodic chitsulo ndi anodic zokutira mkuwa.
Nthawi zambiri amagwiritsidwa ntchito kuteteza zokutira zokongoletsa kuti apewe dzimbiri ndikuwonjezera kukongola. Kuyika kwa nickel pazinthu zamkuwa ndikoyenera kupewa dzimbiri, koma chifukwa cha kukwera kwa faifi tambala, ma aloyi amkuwa amagwiritsidwa ntchito m'malo mwa nickel plating.
Nthawi yotumiza: Nov-14-2024
