what's the difference between GI and GL

Galvanized(GI) and galvalume(GL) are two common metal anti-corrosion treatment methods, and they have some differences in materials and application fields.

• Galvanizing: Coating zinc on the surface of iron or steel to form an iron-zinc alloy layer.
• Galvalume: Coating zinc and aluminum on the surface of steel to form an aluminum-zinc alloy layer.

• GL has better corrosion resistance than pure zinc. Aluminum element can form a dense oxide film, which can effectively prevent the erosion of oxygen, water and other corrosive media, and provide a longer-term protection effect.
• GI has a good protective effect against corrosion in general environments, but corrosion may occur in more severe conditions, such as marine environments or exposure to acidic and alkaline environments.

• Galvanized usually has a silver-gray appearance.
• Galvalume presents a silver-white appearance.

Galvalume is more difficult to machine than galvanized, and due to the aluminum content, machining galvanized steel may require greater force or special processes.

• Galvanized: commonly used in building structures, pipes, metal products and other fields. Suitable for general anti-corrosion requirements and normal environmental conditions.

• Galvalume: Widely used in environments that require higher corrosion resistance, such as marine environments, chemical equipment, roofs, facades, etc. Where exposure to harsh weather conditions or where longer-term protection is desired, galvalume is the more common choice.