Aluminized Steel Sheet

Updated: 2026-09-15

Overview

Aluminized Steel Sheet is a composite material consisting of a carbon steel substrate coated with an aluminum or aluminum-silicon alloy layer through a continuous hot-dip process. This coating provides exceptional corrosion protection while maintaining the structural strength of steel. The material combines the best properties of both metals - the durability of steel and the oxidation resistance of aluminum. The coating thickness typically ranges from 20-40 microns, with two main variants: Type 1 (pure aluminum coating) and Type 2 (aluminum-silicon alloy coating). Type 2 offers better adhesion during forming operations. The product is manufactured under strict quality standards including ASTM A463 in the US and EN 10346 in Europe.

Physical and Chemical Properties

The aluminum coating forms a protective oxide layer that prevents rust formation, offering 3-7 times better corrosion resistance than galvanized steel in most environments. The material can withstand continuous exposure to temperatures up to 450°C (Type 2) while maintaining its protective properties. Its thermal reflectivity reaches 80% for infrared radiation, making it ideal for heat management applications. Mechanically, aluminized steel maintains the strength characteristics of its base steel (typically 250-550 MPa tensile strength) while gaining enhanced oxidation resistance. The coating provides good formability, allowing bending angles up to 180° without flaking when proper tooling is used. The electrical conductivity is approximately 30-40% that of pure aluminum.

Main Applications

In automotive manufacturing, aluminized steel accounts for about 70% of exhaust system components due to its resistance to salt and high-temperature oxidation. Heat exchanger manufacturers use it for air conditioner condensers and industrial heat recovery systems where thermal conductivity and corrosion resistance are critical. The construction industry utilizes aluminized steel for roofing, wall panels, and chimney liners where its weather resistance outperforms regular galvanized steel. Appliance manufacturers specify it for oven cavities, water heater tanks, and dryer drums. Emerging applications include solar thermal collectors and biomass boiler components where long-term durability in harsh environments is required.

Safety and Storage

Aluminized steel requires no special handling precautions beyond those for regular steel sheet products. The aluminum coating presents minimal health risks during normal fabrication processes. However, welding and thermal cutting operations require proper ventilation as they may produce aluminum oxide fumes. For storage, keep sheets dry and elevated from the floor to prevent moisture accumulation. Stack with proper separators to avoid coating damage. Indoor storage is preferred; if outdoor storage is necessary, use waterproof coverings and ensure good air circulation to prevent condensation. The material is non-flammable and doesn't require special fire protection measures.

B2B Procurement Guide

When sourcing aluminized steel, specify the coating type (pure Al or Al-Si alloy), coating weight (typically 60-150 g/m² total both sides), and base steel properties (strength grade, surface finish). Type 2 Al-Si coating (5-11% silicon) is preferred for formed parts, while pure aluminum coating offers better corrosion protection for static applications. Lead times typically range from 2-8 weeks depending on specifications and mill schedules. Consider ordering from mills with CGL (Continuous Galvanizing Line) capabilities that can produce both galvanized and aluminized products. For large projects, negotiate pricing based on quarterly aluminum ingot prices plus processing fees. Quality certifications to request include mill test certificates confirming coating weight and mechanical properties.