Spangle is a unique and desirable feature that appears on galvanized steel during the hot-dipped galvanizing process. It occurs when liquid zinc cools and solidifies, resulting in crystal grains forming on the steel's surface. These crystal grains create a beautiful snowflake or hexagonal star appearance that adds visual appeal to the steel. That is spangle on galvanized steel.
The size, brightness, and topography of the spangle depend on various factors, including the composition of the zinc layer and the cooling method used during the galvanizing process. At GNEE Steel, we are able to offer big, regular, and zero spangle galvanized steel, giving you the flexibility to choose the look that best suits your needs. Contact us today for more information!
Types of Spangle on Galvanized Steel
According to American Standard (ASTM A653), it can be divided into galvanized steel with normal spangles (N), minimum spangles (M), and zinc-free spangles (F). Chinese standard (GB/T 2518) is similar to ASTM. While according to the European standard (EN10346:2015), the galvanized spangle can be divided into normal spangle (N) and minimized spangle (M). Japanese standard (JIS G3302) is close to the EU standard.
| Standard | Chinese Standard (GB/T 2518) | American Standard (ASTM A653) | European Standard (EN10346:2015) | Japanese Standard (JIS G3302) |
| Steel Grade | DX51D+Z | DC51D+Z | DX51D+Z | SGCC |
| Code | N (normal spangle) | N (normal spangle) | N (normal spangle) | R (regular spangle) |
| Definition | Do not control the solidification process of the zinc layer to form various sizes of spangles during the natural solidification process. | Spangles are obtained when the zinc coating is naturally solidified. There will be spangles of different sizes and brightness. But the quality of the galvanized layer will not be affected. | Spangles formed during the crystallization and solidification of the zinc layer. | |
| Code | M (minimum spangle) | M (minimum spangle) | M (minimized spangle) | |
| Definition | Control the solidification process of the zinc layer to obtain relatively uniform and small spangles, which are still visible to the naked eye. | Fine spangles are obtained by controlling the solidification process of the zinc layer in a special way. Usually, the spangles are invisible to the naked eye. | ||
| Code | F (zinc-free spangle) | F (zinc-free spangle) | Z (zero spangles) | |
| Definition | Tiny spangles are invisible to the naked eye by controlling the solidification process of the zinc layer. | To control normal spangle formation to a small value. | ||
Hot Dipped Galvanized Sheet
Different Applications of Galvanized Metal with Spangle
In fact, spangles only offer different surface appearances. But it will not influence the quality of zinc coating. However, as the base metal of prepainted galvanized steel coil, spangles will influence its painting adhesion and corrosion resistance. Therefore, small or zero-spangle products are better for the home appliance and automobile industries. While galvanized steel with normal spangle is often for general purposes and the construction industry. If you have special requirements for spangles, please inform the supplier in advance.