Galvanizing is also called hot dip galvanized, it is a widely used process against corrosion of metal coating. SGCC brand originated from the Japanese industrial standard JIS G3302, some think this is a hot dipped with pure zinc galvanized coating and ignore its suffix. In fact, according to its different suffix, there are also hot-plated pure zinc and hot-galvanized ferroalloy products.
Pure-zine coating galvanized steel sheet is the most economical type of anti-corrosion coating, which is obtained by hot-dip dipping pre-treated galvanized steel strip in molten zinc. Pure zinc-coated steel sheets can be divided into spangle-free and steel sheets, which offer the same corrosion resistance to plastering. Non-sequin products don't need to be sprayed or painted, while heavy-duty zinc-coated products are usually made with zinc spangle. The zinc content in zinc solution should not be less than 99%.
Zinc-iron alloy plate is a galvanized alloy sheet. After hot dipping in a zinc pot, the steel plate or plate is subjected to a short heat treatment in an alloy furnace to cause a chemical reaction between the Zn and Fe to form a zn-fe alloy coated steel plate. Alloy process in 5~10 seconds to make galvanized stainless steel by heating to 550~560°C in the furnace and produce the iron-zinc alloys. Such an alloy treatment forms a zinc-iron alloy coating on the coating with an 8~15% Fe. The galvanized steel sheet steels can be made into high-temperature alloy or superalloy, corrosion-resistant alloy, high-strength alloy, electric vacuum alloy and other materials with special properties. Weldability, coating properties, heat resistance and corrosion resistance of galvanized steel sheet alloy are better than those of ordinary hot dipped galvanized steel sheet.
The pure zinc-coated sheet and zinc-Fe alloy coated steel plate is the same requirement of zinc content in common, the difference is that alloy coil hot-dipped adding an alloy process, forming two products.
Both the European standard DX51D and the Japanese standard SGCC have zinc-iron and pure zinc coatings that need to be carefully identified. The European standard generally uses "+Z" or "+ZF" to distinguish between zinc-iron and pure zinc alloy coatings. For example, EN 10346 DX51D+Z is pure zinc; EN 10346 DX51D+ZF is a zinc-iron alloy coating. In the JIS standard, the type of zinc layer is placed together with the zinc layer thickness indicator. Such as: JIS G3302 SGCC Z06 is the double pure zinc coating with 60g/㎡thickness, JIS G3302 SGCC F06 is double sided zinc alloy with the thickness of 60 g/㎡. The table below lists the details of JIS G3302 SGCC coating material:
|
SGCC Coating |
Material |
Features |
|
Pure-zine coating |
Z06 Z08, Z10, Z12, Z14, Z18, Z20, Z22, Z25, Z27, Z35, Z37, Z45, Z60 |
Light coated products have good weldability andformability. Heavy-duty coated products have superior corrosion resistance. Wide application are possible by selecting sequin or a post treatment. |
|
Alloy coating |
F04 F06, F08, F10, F12, F18 |
Zn-Fe alloy coated by hot dip galvanizing and annealing. Zn-Fe coating has superior paint adhesion and corrosion resistance. The weldability is superior to pure-zine products. |
