Product details table:

Physical and chemical properties:

Physical properties

Appearance:

Galvanized steel coils typically present a metallic silver-gray color with a smooth surface and a shiny finish due to the zinc coating. The surface can have different textures depending on the galvanization process, such as regular spangle, minimized spangle, or zero spangle finishes.

Density:

The density of galvanized steel coils is generally around 7.85 g/cm³, which is slightly higher than stainless steel due to the added zinc layer. However, the exact density may vary depending on the thickness of the zinc coating.

Melting point:

The melting point of galvanized steel is approximately 1300-1400℃, depending on the composition of the base steel and the zinc coating. The zinc coating itself melts at around 420℃, but the steel substrate remains stable at higher temperatures, providing good performance in elevated temperature environments.

Coefficient of thermal expansion:

The coefficient of thermal expansion for galvanized steel is relatively low, similar to carbon steel, at about 11-13×10⁻⁶/℃. This property allows it to maintain dimensional stability even in environments with significant temperature fluctuations.

Thermal conductivity:

The thermal conductivity of galvanized steel is moderate, with values ranging from 45-55 W/(m·K). While not as high as copper or aluminum, its thermal properties are sufficient for most structural and industrial applications.

Electrical conductivity:

Galvanized steel has lower electrical conductivity compared to pure metals like copper or aluminum. Its conductivity is influenced by the zinc coating, making it unsuitable for primary electrical applications but still useful in grounding systems and other low-conductivity needs.

Chemical properties

Corrosion resistance:

One of the key features of galvanized steel coils is their excellent corrosion resistance. The zinc coating acts as a sacrificial anode, protecting the underlying steel from rust and corrosion. This makes galvanized steel ideal for outdoor and humid environments, such as roofing, fencing, and automotive parts. In marine environments, additional protective coatings may be required to enhance durability.

Antioxidation:

Galvanized steel exhibits good oxidation resistance due to the protective zinc layer. However, prolonged exposure to extremely high temperatures can cause the zinc coating to degrade, reducing its antioxidation properties over time.

Chemical stability:

In general, galvanized steel is chemically stable and resistant to mild acids, alkalis, and atmospheric conditions. However, in highly corrosive environments, such as exposure to strong acids (e.g., sulfuric acid) or alkalis, the zinc coating may deteriorate, affecting the steel’s long-term performance.

Passivation:

Although galvanized steel does not undergo traditional passivation like stainless steel, the zinc coating provides a natural form of protection against corrosion. Over time, the zinc reacts with oxygen and carbon dioxide in the atmosphere to form a protective layer of zinc carbonate, further enhancing its resistance to environmental damage.

Application:

Galvanized steel coils are widely used across various industries due to their excellent corrosion resistance, durability, and cost-effectiveness. In the construction industry, they are commonly used for roofing, wall cladding, and structural components. In the automotive sector, they are utilized for manufacturing car frames and panels. They are also essential in the production of household appliances, such as refrigerators and washing machines, due to their aesthetic appeal and protective qualities. Additionally, galvanized steel is used in agricultural equipment, HVAC systems, and infrastructure projects, where resistance to weathering and corrosion is critical.