What is Corten Metal?
Corten, also known as weathering steel, is a high-strength steel alloy renowned for its distinctive rust-like appearance. This unique weathered look develops over time as the metal is exposed to weather conditions, creating a protective layer that prevents further corrosion. This self-protecting quality makes Corten an ideal choice for various applications, particularly in architectural and outdoor settings.
SECULAR CHANGES IN RUST APPEARANCE
- Why Choose Corten?
- Aesthetic Appeal: The natural, evolving patina of Corten steel adds a striking visual element to any project. Its earthy tones blend seamlessly with natural landscapes and urban environments alike, making it a popular choice for architects and designers.
- Durability: Corten steel is designed to withstand the elements, making it exceptionally durable and long-lasting. Its weather-resistant properties reduce the need for maintenance, ensuring that your projects remain beautiful and intact over time.
- Versatility: Perforated Corten sheets can be used in a variety of applications, from flooring to cladding.
Considerations for using Corten?
Initial Appearance: Before the patina forms, Corten appears like ordinary steel. The transformation to its characteristic weathered look is gradual.
Patina Development: Corten steel forms a protective rust-like patina over time when exposed to weather. This process can take several months to a few years, depending on the environmental conditions.
When using COR-TEN steel for Architectural purposes, the ‘stabilising’ process is an important consideration. To minimise rust stain due to the ‘runoff’ of rust in the initial weathering stages the panels must be some way stabilised before being installed on site.
The weathering process can be quickened through various processes including pickling. Graepels recommend ordering perforated Corten in advance of installment as ‘stabilisation’ of the panels can take between 2-6 months when leaving it weather ‘naturally’.
For the weathering process to occur properly, Corten steel must be exposed to alternating wet and dry conditions. Constant moisture or immersion in water can prevent the patina from forming correctly.
Marine and Humid Environments: In highly humid or marine environments, Corten may corrode faster and more unevenly. Special considerations or treatments may be needed in such settings.
Minimal Maintenance: Once the patina has fully developed, Corten steel requires little to no maintenance, as the protective layer prevents further corrosion.
Galvanic Corrosion: When Corten steel is in contact with dissimilar metals, galvanic corrosion can occur. Care should be taken to avoid direct contact with metals like aluminum, zinc, or stainless steel unless proper isolation techniques are used.
Load-Bearing Capacity: Corten steel is strong and durable, but its thickness and structural properties should be calculated for load-bearing applications to ensure safety and stability.
Appearance Preferences: Corten is the marmite of the materials world, its’ rusty appearance is not appealing to everyone and can clash with certain design aesthetics thus an important consideration.
Advantages of Perforated Corten
Perforated Corten sheets are strong, durable and are used in many architectural applications, however, weight is an important consideration as Corten is substantially heavier than Aluminium even when perforated.
However, this weight makes it ideal material for applications where a more durable and stronger material is required.
Perforated Patterns: There is huge flexibility to perforated patterns, hole shapes and sizes these holes and patterns can be punched into most material types including Corten.
Perforation Type: Perforated metal typically refers to punched metal holes flush with the sheet, however, raised edges and countersunk holes among others are possible within the perforation process. Each hole type serves a purpose, for example raised perforations can facilitate with grip.
Drainage: Perforations allow for drainage due to the holes as mentioned above Graepels can offer a range of ‘perforations types’ such as countersunk or ‘raised’ perforations to facilitate drainage and grip.
Grip: Once corroded a concrete type of texture forms on the surface giving added grip making it ideal for Perforated flooring providing drainage, texture, and grip
Applications: Corten is a structural steel it has a higher tensile strength to other everyday steel perfect for perforated flooring, fencing and public sculptural pieces
Fabrication: Corten is easy to form, perforate and weld.
Advantages of Corten Woven Wire
Aesthetic Appeal: Corten woven wire has a distinctive rustic appearance due to the weathered look of Corten steel. Often mistaken for rust, this earthy finish is a patina which protects the metal.
Durability: The inherent properties of Corten steel provide enhanced durability and resistance to atmospheric conditions, making it suitable for outdoor applications.
Versatility: Available in various mesh sizes and patterns, Corten woven wire can be used for both functional and decorative purposes in construction and landscaping.
Durability and Strength: Weaving Corten steel into wire mesh can be challenging for some manufacturers due to its material properties being stiffer and harder compared to softer metalslike aluminum or mild steel. This can make the weaving process more labor-intensive and require stronger equipment.
Graepels are one of the few weavers manufacturing Corten woven wire mesh. We understand that using the appropriate gauge of wire is crucial. Thinner gauges are easier to weave but may not provide the same structural integrity. Balancing the wire thickness with ease of weaving is necessary.
Self-Healing Surface: Small scratches and abrasions on Corten steel heal over time as the oxide layer reforms, maintaining its protective qualities.
Application suitability: Corten Woven Wire for Architectural and Decorative applications is often used for projects where aesthetic appeal and integration with the environment are crucial, such as building facades, landscape features, and artistic installations.
