Galvanized steel coil is a kind of steel that has been treated with hot-dip galvanizing or electro-galvanizing. It is widely used in construction, home appliances, automobiles and industrial equipment.
The base material of galvanized steel coil is usually low-carbon steel. After hot-dip galvanizing or electro-galvanizing, a layer of zinc or zinc alloy coating is formed on the surface. The following is a typical composition:
Base material composition:
C: 0.02%-0.10%
Mn: 0.20%-0.50%
P, S: ≤ 0.03%
Other trace elements: Si, Al, N, etc.
Coating composition:
Pure zinc coating: mainly Zn, the coating mass is generally 60g/m² to 275g/m².
Alloy coating: such as zinc-iron alloy (Galvanneal), zinc-aluminum alloy (Galvalume), in which Zn accounts for the vast majority, but contains Fe, Al and other elements.
The grades of galvanized steel coils vary from country to country and from standard to standard. Here are some common grades and their corresponding standards:
Chinese Standard (GB/T 2518-2008):
DX51D+Z, DX52D+Z, DX53D+Z, DX54D+Z (indicates structural grade and deep drawing grade)
SGCC, SGCH (indicates structural grade and high-strength structural grade)
European Standard (EN 10346):
DX51D+Z, DX52D+Z, DX53D+Z, DX54D+Z
S220GD+Z, S250GD+Z, S280GD+Z, S320GD+Z, S350GD+Z (for construction)
Japanese Standard (JIS G 3302):
SGCC, SGCD1, SGCD2, SGCD3
SGC340, SGC400, SGC440 (high-strength structural steel)
American Standard (ASTM A653/A653M):
CS (Commercial Steel), FS (Forming Steel), DDS (Deep Drawing Steel), EDDS (Extra Deep Drawing Steel)
Structural Grades: SS33, SS37, SS40
Galvanized steel coils have the following characteristics:
Strong corrosion resistance: The zinc layer effectively protects the steel substrate and prevents rust.
Bright appearance: The surface is smooth and can be passivated or coated according to needs.
Good forming performance: Especially the deep drawing grade, suitable for various stamping forming processes.
Weldability: The weldability is relatively good, but attention should be paid to the effect of the coating thickness on welding.
Economical efficiency: Compared with other anti-corrosion methods, such as stainless steel or coated steel plates, galvanized steel coils have a higher cost-effectiveness.
According to the different specifications and properties of galvanized steel coils, it is widely used in the following fields:
Construction industry: used for roof panels, wall panels, keels, gutters, fences, etc.
Home appliance industry: refrigerators, air conditioners, washing machines, etc.
Automotive industry: body panels, chassis, internal structural parts, etc.
Light industry: home appliances, furniture, pipes, containers, etc.
Galvanized steel coil is an indispensable and important material in industrial production and construction due to its excellent corrosion resistance and processing performance. Different grades and coating designs make it show excellent performance in different application scenarios.
