About COR-TEN®

COR-TEN®, often referred to as weathering steel, is a group of steel alloys developed to eliminate the need for painting and form a stable rust-like appearance after exposure to weather. The name, COR-TEN®, is a trademark of U.S. Steel and derives from its two primary properties: “CORrosion resistance” and “TENsile strength”. This type of steel is renowned for its unique ability to form a protective layer of rust, which significantly reduces corrosion rates compared to standard steel.


The composition of COR-TEN® steel includes:

  • Carbon (C): Less than 0.12%
  • Copper (Cu): Between 0.25% and 0.55%
  • Chromium (Cr): Between 0.30% and 1.25%
  • Nickel (Ni): Between 0.65% and 0.95%
  • Manganese (Mn): Between 0.95% and 1.35%
  • Phosphorus (P): Less than 0.04%
  • Silicon (Si): Between 0.25% and 0.75%
  • Sulfur (S): Less than 0.03%
  • Iron (Fe): Balance

The unique blend of these elements allows it to develop a stable, rust-like patina when exposed to weather, which acts as a protective barrier against further corrosion.

Common Applications

Perforated COR-TEN® metal is used across various industries due to its durability, aesthetic appeal, and minimal maintenance needs. Here are some key applications:

1. Architectural and Design:

  • Façades and Cladding: The distinctive rust-like appearance of the metal makes it a popular choice for building exteriors, offering a modern, industrial look that blends with natural surroundings.
  • Sculptures and Art Installations: Artists and designers use perforated COR-TEN® for its unique visual appeal and longevity.

2. Infrastructure:

  • Bridges and Overpasses: Its high tensile strength and corrosion resistance make it ideal for structural applications.
  • Railcars and Shipping Containers: The durability and weather resistance of COR-TEN® help extend the lifespan of these transport solutions.

3. Landscaping:

  • Retaining Walls and Planters: The material’s resistance to corrosion ensures long-lasting performance in outdoor environments.
  • Fencing and Gates: Perforated COR-TEN® provides both security and aesthetic value in landscape design.

4. Industrial:

  • Mining and Industrial Equipment: COR-TEN® is used in environments where high durability and resistance to weathering are critical.


While COR-TEN® offers many advantages, it also has certain limitations:

  • Initial Rust Runoff: When the metal first begins to rust, there can be an initial period where the rust washes off, which can stain surrounding surfaces. This requires careful consideration in design and placement.
  • Salt Exposure: COR-TEN® is less effective in environments with high salt concentrations, such as coastal areas, where the protective patina can be compromised, leading to accelerated corrosion.
  • Cost: COR-TEN® steel can be more expensive than traditional steel, which might impact budget considerations for some projects.

Example of Using COR-TEN® as an Architectural Element:

The Barclays Center in Brooklyn, New York, showcases a striking facade made from perforated COR-TEN® steel. This weathering steel was chosen for its unique aesthetic and durability, forming a rust-like patina that evolves over time. The distinctive design consists of 12,000 pre-weathered steel panels, creating an eye-catching, organic appearance that complements the urban environment. The use of this material not only enhances the visual appeal but also ensures low maintenance and longevity, reflecting the Center’s modern, industrial character while blending seamlessly with the surrounding landscape. This innovative application highlights the material’s architectural versatility and enduring beauty.

Roy Manufacturing is your source for COR-TEN® to bring your project to life.

COR-TEN® is a versatile and durable material, ideal for various applications where corrosion resistance and aesthetic appeal are desired. Its unique composition allows it to form a protective rust layer, reducing maintenance and extending the life of the material.

As a perforated metal solution, COR-TEN® offers a blend of functionality and visual appeal, making it a popular choice in modern architecture, infrastructure, and industrial design.

Contact Roy Manufacturing today for a free estimate on your project. We are your premier supplier of perforated metals and materials for industrial parts, architectural applications, commercial products, and more.