What Is Aluminized Steel?

Aluminized steel combines the strength of steel with non-corrosive properties of aluminum. A process similar to galvanizing is used in its production: coating steel pieces with aluminum and silicon solutions before rolling over them with another sheet of metal.

Type 1 aluminized steel is widely utilized in industrial settings for applications including jacketing over insulation, pipes carrying corrosive substances and automotive mufflers. Furthermore, its excellent heat reflection properties reflect up to 80% of radiant heat hitting it directly.

Corrosion Resistance

Aluminization adds an aluminum alloy coating to steel, increasing its durability and corrosion resistance. Thin layers of aluminum and silicon help to protect underlying steel from oxidizing, thus preventing pitting. Aluminized steel is resistant to most acids (salts) which would corrode most other metals, and also serves to shield it from moisture, air pollution and chemicals like oxygen and water.

Due to its excellent heat resistance, aluminized steel is frequently utilized as cladding in oil and gas facilities and pipelines, fire protection systems and insulation applications. Furthermore, its strong build means it is great for fire mufflers as well as insulation applications and more durable than stainless steels which may deform under extreme temperatures.

Due to its lower cost, aluminized steel makes an economical alternative to more costly materials like stainless steel. Furthermore, its aluminum-silicon coating has excellent thermal properties, reflecting up to 80% of radiant heat away from its surroundings – helping lower operating costs and decrease energy usage.

Aluminized coatings are constructed from an aluminum-silicon alloy, and therefore offer great flexibility when it comes to shaping them into various shapes and sizes. Cutting it easily allows it to be rolled up into tubes or sheets – perfect for applications where space is at a premium. This material makes an excellent addition for industrial settings where space may be at a premium.

Aluminized steels are much cheaper than their stainless counterparts due to being constructed primarily of plain carbon steel, with only 30 to 270 grams per square meter or 0.10 to 0.90 ounces per square foot of surface area added with aluminum-alloy coating (compared with around 3 times as much for stainless steels).

Type 2 aluminized steel is hot-dip coated with commercially pure aluminum for atmospheric corrosion resistance applications such as enclosures for sewage piping, corrugated roofing and siding, grain bins, drying ovens and air-conditioner condenser housings. In addition to offering corrosion resistance properties, Type 2 also boasts superior thermal properties and heat reflectivity properties that make it suitable for many industries.

High Temperature Resistance

Steel is a durable material that stands up well in tough environments, yet over time can oxidize or rust over time. Aluminized steel’s aluminum coating prevents this from happening, keeping its strength and durability even under high temperatures. Aluminized steel makes an excellent material choice for applications like corrugated roofing and siding panels, grain bins, air-conditioner condenser housings and drying ovens – industrial applications of this nature require durability for maximum longevity.

Aluminizing creates a tight metallurgical bond between carbon steel and an aluminum-silicon alloy coating, offering superior resistance against heat and corrosion compared to galvanized steel, while being capable of withstanding higher maximum temperatures than stainless steel.

This process produces insulation properties in aluminized steel that allow it to reflect up to 80% of radiant heat, helping keep metal cool in high-heat environments. Aluminized steel’s ability to withstand high temperatures while remaining corrosion resistant makes it the perfect material for manufacturing equipment and components.

Aluminized steel offers several benefits over stainless steel, particularly its lower thermal expansion coefficient. This makes it less likely to deform under stress and make it an excellent choice for structural and mechanical applications such as structural support for gas plants or power stations. Furthermore, its ease of cutting makes it an economical solution when used for jacketing insulation systems in applications like petrochemical plants and gas stations.

Aluminized steel is highly formable, offering flexible shaping capabilities such as being bent, rolled or corrugated for deep drawing capabilities and easy welding procedures. Furthermore, its versatile nature enables its use across a variety of projects and applications.

Aluminized steel comes in various sizes and forms, from coils and sheets to factory-bonded moisture barriers (DryMet) or mass loaded vinyl acoustic barriers bonded directly onto the steel (SoundMet). AK Steel also offers various yield strengths according to application, customizing coil sizes or sheets according to customer needs.

Heat Reflectivity

Aluminized steel’s coating reflects up to 80% of radiant heat that strikes it, making it an efficient thermal conductor and perfect for use as insulation cladding in industrial settings such as furnaces, oil refineries and gas plants. Furthermore, its surface provides superior protection from atmospheric corrosion, salt spray corrosion and muffler condensate corrosion than galvanized or stainless steel counterparts.

Aluminized steel can be custom tailored to any application with different coating options that best meet its purpose. For example, type 1 aluminized steel features an aluminum-silicon coating containing between 5-11% silicon that helps it withstand high temperatures while resisting corrosion – ideal for baking pans, water heaters, ovens ranges space heaters or vehicle mufflers.

Type 2 aluminized steel features a commercially pure aluminum coating with thicker thickness than type 1’s coating and is often used for industrial cladding and jacketing over insulation, structural applications such as enclosures and sewer piping, as well as for environmental corrosion resistance in outdoor settings with frequent exposures. Its commercial purity also makes this grade ideal for resistance against atmospheric corrosion when used outdoors compared with stainless or galvanized steel options.

Both Type 1 and 2 Aluminized steels are offered with factory bonded Surlyn moisture barriers or mass loaded vinyl acoustic barriers bonded directly onto them (DryMet and SoundMet respectively) that reduce water penetration into their surfaces, protecting against corrosion.

Aluminizing is an expansive process that can be performed on various base metals. Carbon and low-alloy steel are often chosen as suitable bases, since their properties allow aluminum coatings to adhere well. Aluminizing can be accomplished using electroplating or metal spraying – with electroplating using electric current to deposit aluminum ions onto its surface while metal spraying uses high pressure streams of molten aluminum coating the workpiece directly.

Lightweight

Aluminum coating applied to steel sheet through the aluminizing process only adds about five percent more to its weight compared with total components weight; this may seem insignificant but engineers searching for ways to minimize product footprint can find this change important when striving to minimize their product’s environmental footprint.

When product designers want to reduce weight, they typically turn to one of three materials: stainless steel, aluminum or hot-dip aluminized steel sheet. Each has their own advantages and drawbacks; aluminized steel is particularly well suited for situations involving high temperatures.

This is because aluminized steel combines the corrosion resistance and heat reflectivity of aluminum with the strength and cost-effectiveness of steel, making it an excellent material to use for applications requiring high temperature environments such as kilns and drying ovens. Aluminized steel can also be found in numerous appliances used across small appliances, major appliances and industrial production equipment.

Hot-dip aluminized steel sheet typically comprises Type 1 and Type 2 carbon steel that have been coated, through the hot dip process, with commercially pure aluminium (usually between 5%-11% silicon), creating an intermetallic layer which strengthens and improves adhesion to their base metals. Coating thickness ranges between 300g/m2 for Type 1 sheets up to 650g/m2 for Type 2, which may also feature factory bonded moisture barriers like Surlyn’s DryMet and SoundMet.

Aluminized steel has long been revered for its superior durability compared to lightweight metals like magnesium and titanium. Durable aluminized steel often proves more cost-effective as stamping operations are much simpler and its propensity for splitting or cracking during fabrication and assembly is lower.

As more engineers explore alternatives to steel in their design processes, they’re finding innovative uses for lightweight metals like aluminized steel. While not as strong or durable as steel, aluminum, magnesium and titanium remain viable solutions when stress-bearing components need to be lightened without losing structural integrity.