Anvan reponn sa agalvanizasyon question, let's have a basic understanding the composition of the steel. First of all, the predominant element is iron, and it's soft and ductile. By adding around 0.5 percent carbon to iron, it can dramatically increase tensile strength of the iron. In addition to carbon, manganese also increases hot working properties and increases hardenability and toughness of steel. In general, alloy steels have different material properties which lead to different mechanical performance. Oxygen reacts with and consumes the carbon, to solve this problem, silicon is added to iron as a deoxidizing agent. With excessive quantity of silicon, it can create rough galvanization coating.
Fosfò yo pèmèt pa nivo maksimòm jiska {{0}}.04 pousan, si pi wo pase 0.04 pousan, li ka ogmante tandans pou asye fann pandan soude ak kreye ki graj kouch galvanised. Tou de fosfò ak Silisyòm ka aji sinèrjetik pou lakòz kwasans rapid nan kouch alyaj zenk -fè nan kouch galvanize paske yo aji kòm katalis pandan pwosesis galvanizasyon an. Foto ki anba a se yon egzanp tipik nan sifas galvanizasyon ki graj ki te koze pa twòp nan kontni Silisyòm.
Pou reyalize yon sifas galvanizasyon son, dapre ASTM A385 oswa ISO 1461, eleman enpòtan sa yo bezwen kenbe nan yon nivo ki nan lis anba a:
√ Ckontni arbon mwens pase 0.25 pousan
√ Manganèz mwens pase 1.3 pousan,
√ Silicon mwens pase {{0}}.04 pousan oswa ant 0.15 pousan ak 0.24 pousan
√ Posfò mwens pase 0.04 pousan .
What if silicon content is not in line with the above suggested range, and what could happen to the galvanization? The answer lies in the Sandelin Curve The conclusion is rather clear, and slope is very steep when the silicon is around {{0}}.05 percent , and this level of silicon content usually lead to very thick zinc coating thickness with dull grey appearance. Based upon Sandelin Curve, the recommended limits for silicon is either below 0.04 percent or between 0.15 percent and 0.24 percent .
In reality, lots of galvanizers don't really care that much about either silicon content or Sandelin Curve, and they primarily use dipping time to control the galvanization thickness. This wrong practice normally lead to lots of domaj galvanizasyon, such as rough surface, thin galvanization coating which is not in line with ISO 1461 requirement.
Kontni Silisyòm dwat la ka gen anpil son ak epesè kouch epesè, epi li ka bay bon pwoteksyon kont korozyon, ak Se poutèt sa lanmè,agrikilti, akwakilti, telekominikasyon, min ak tinèl projects require very accurate control on silicon content.
Aktyèlman, yon sètifika moulen asye pral ede galvanizers filtre deyò materyèl la ki pa kalifye yo dwegalvanize plonje cho, and it will save costs for both galvanizers and the steel fabricators.
