The term’galvanizing’broadly identifies an electro-deposition process in which a thin layer of another metal is put into something made from steel. The goal of galvanizing is to protect the base steel by preventing rusting. However, one of the utmost effective galvanizing methods doesn’t employ any electrochemical deposition. It is known as hot dip galvanizing or simply HDG.
Hot dip galvanizing is becoming widely popular owing to its effectiveness when it comes to corrosion protection. In fact, in recent times, the term “galvanizing” is being used to reference hot dip galvanizing. In this approach, a four-layer corrosion resistant finish or surface is produced on a steel base using zinc by an electrochemical process. The metal (usually steel and iron) to be protected from corrosion is passed by way of a molten bath of zinc at a temperature of 460 degree centigrade. Zinc bonds to steel at the molecular level. Of four layers created, while the very best layer is zinc, the three layers underneath are composed of zinc-iron alloy. HDG is being extensively useful for industrial applications requiring the effectiveness of steel and effective resistance to corrosion.
Hot dip galvanizing has which may be a lot more superior in comparison with other methods like use of paint, metallizing, mechanical galvanizing or electroplate galvanizing. It has emerged as you of the very most result-oriented and reliable techniques that fits your entire galvanizing requirements hot dip galvanizing. Unlike electroplate galvanizing (which is considered to be the first form of galvanizing), HDG produces a much thicker, durable coating rendering it ideal for even outdoor applications. On the other hand, the thin coating created by electroplating is much faster consumed, exposing the steel base to corrosion.
HDG results in superior protection from corrosion or rusting. The hard zinc-steel alloy layers offer an effective barrier. If this barrier is damaged, zinc acts as a sacrificial anode; the electrons in the zinc coating will sacrifice themselves to avoid corrosion. Additionally, the topmost layer comprising only zinc, when reacts with the oxygen, moisture and carbon dioxide in the air, forms a thin but hard film called the zinc patina (which is obviously an impermeable layer of zinc carbonate). It acts as an effective barrier on the galvanized zinc coating and protects it from corrosion. Zinc is more reactive than iron or steel and therefore the zinc galvanized coating corrodes first, protecting the base metal.
Because hot dip galvanizing results in bonding of zinc to steel at a molecular level, the galvanized coating easily covers the entire surface, including joints, scratched and holes. HDG is widely found in several applications including automotive body parts, handrails, consumer appliances to roofing and walling. Due to the superior corrosion resistant properties, HDG is increasingly used to protect the surface automotive parts and panels. Hot-dip galvanized steel strip is also commonly found in metal pails, and heating and cooling duct systems in buildings.