Hot-dip galvanizing is the best protective coating solution available for steel-based materials.
A tried and tested technique, the history of hot dip galvanizing dates as far back as 1742. It was in this year that French chemist Melouin recorded a process of dipping iron into molten zinc in order to create a zinc coating. However, the actual term “galvanizing” was not applied to the process of coating steel until 1837 when French engineer Stanislas Sorel filed a patent for the galvanic process.
The main purpose of galvanizing is to protect steel from corrosion. When dipped in a bath of molten zinc, the steel reacts with the zinc creating an alloy that metallurgically bonds to the surface of the steel. Layers of zinc then form on top, providing a tough, abrasion-resistant coating.
The life expectancy of hot-dip galvanized products may differ depending on atmospheric conditions and the regularity of maintenance carried out on the product. With more data becoming available over the years we can now look at AS 4312-2008 Atmospheric corrosivity zones in Australia. When introducing hot-dip galvanizing products in a particular zone, atmospheric conditions and exposure level should be taken in to consideration. Contaminants in the atmosphere from industrial activities, and chlorides in the air due to relative positioning to the ocean, can create higher rates of corrosion on protective coatings.
Zinc-iron alloy coatings are formed when molten zinc reacts with elements of the steel’s surface in the galvanizing bath at a nominal operating temperature of 450°C. Hunter Galvanizing provides hot-dip galvanized coatings with zinc iron alloy layers in most cases harder than the base metal upon which they are applied. An average coating mass of 600g/m2 is achieved on fabricated items of steel thickness 6mm (and greater) in accordance with AS/NZS 4680.
Further information can be found by clicking the image above or sending an email to enquires@huntergal.com.au