Corten steel grades are types of weathering steel that form a protective rust-like patina when exposed to the elements, enhancing corrosion resistance without the need for painting. Corten A is ideal for architectural facades and decorative elements due to its quick-forming patina, while Corten B offers higher strength for heavy structures like bridges. European grades such as S355J0WP and S355J2W provide good weldability, toughness, and impact strength for structural applications. Corten steel is valued for its durability, low maintenance, and distinctive weathered appearance, making it suitable for various functional and aesthetic projects.
What is Corten Steel?
Corten Steel, also known as weathering steel, is popular in construction because of its unique look and durability. It develops a reddish-brown rust layer when exposed to the elements, which protects the steel underneath and requires little maintenance. This rust layer adds to its distinct appearance and lasts for over 40 years.
Corten Steel is known for its strong resistance to weather and corrosion, making it a great choice for tough environments. Although it can be harder to find than regular steel, its long-lasting and low-maintenance qualities make it a valuable material for building projects. In this blog, we’ll look at the different types and grades of Corten Steel.
Check out the durability and style of Corten steel with Lakshya Steel. We provide a full range of top-quality Corten steel products, including pipes, tubes, fittings, and flanges.
Corten Steel: Weather Resistant and Aesthetic
Corten steel, or Cor-Ten, is a type of atmospheric corrosion-resistant steel known for its durability and unique appearance. As a copper-chromium alloy, it outperforms regular stainless steel in resisting weather-related wear and tear. When exposed to the elements, Corten steel develops a protective rust layer, which not only shields the steel from further corrosion but also gives it a distinctive, visually appealing finish.
This natural rust finish has made Corten steel a favorite among architects for use in building facades, sculptures, and bridges. The protective layer continuously regenerates as it interacts with atmospheric pollutants, ensuring long-lasting performance. However, when using Corten steel for structural purposes, especially in harsh environments, it’s important to carefully consider the thickness to maintain both its strength and aesthetic appeal.
Read More Our Blog: Weathering Steel: Guide to Corten Steel Standards
Corten Steel Grades Offered From Lakshya Steel
Lakshya Steel offers a diverse range of Corten steel products designed for durability and aesthetic appeal. Our selection includes Corten steel pipes, carbon steel fittings, carbon steel flanges, and Corten steel fasteners, catering to various needs and applications.
We provide Corten steel in following two grades:
Corten A Weathering Steel
Corten A is a weather-resistant steel made by blending copper, chromium, and nickel, with a touch of phosphorus. This combination makes it perfect for gas flue applications and attractive building facades. However, it’s not suitable for heavy load-bearing uses, where Corten B or S355J2W would be better choices.
When exposed to the atmosphere, Corten A develops a rust-colored protective layer on its surface. This layer not only requires minimal maintenance but also enhances the steel’s visual appeal, giving it a consistent and attractive finish. This makes Corten A a popular choice for architects and designers looking for both durability and aesthetics in their projects.
Corten A Steel Grades & Equivalents Grades
| Grades | Equivalents |
| CORTEN | EN 10025-5:2004 |
| Corten A | S355JOWP |
Corten A Mechanical Properties
|
Grade |
Thickness (mm) Strip Products |
Plate Products |
Yield Strength Rel N/mm² Minimum |
Tensile Strength Rm N/mm² Minimum |
Elongation A50 % Minimum |
|
Corten A |
2-12 |
6-12 |
345 |
485 |
20 |
Chemical Composition of Corten A
|
Weather resistant steel |
C |
Mn |
P |
S |
Si |
Cr |
Ni |
Mo |
Cu |
|
Corten-A |
0.12 |
0.20-0.50 |
0.070-0.150 |
0.03 |
0.25-0.75 |
0.50-1.25 |
0.65 |
– |
0.25-0.55 |
|
IRS M-41 |
0.1 |
0.25-0.45 |
0.075-0.112 |
0.03 |
0.28-0.72 |
0.35-0.49 |
0.20-0.49 |
– |
0.30-0.39 |
|
ASTM A 588 |
0.2 |
0.75-1.30 |
0.04 MAX |
0.05 |
0.15-0.50 |
0.30-050 |
0.50 MAX |
– |
0.20-0.40 |
Corten B Weathering Steel:
Corten B is a weather-resistant steel designed for heavy and load-bearing structures. When exposed to the elements, it forms a protective layer that helps preserve the steel underneath. This natural rust finish usually eliminates the need for painting or maintenance, making Corten B a cost-effective choice compared to other structural steels. However, in continuously wet conditions, such as at the base of a structure or when partially submerged, regular maintenance and painting may be necessary to prevent corrosion. Despite this, Corten B remains a popular option for robust structures due to its durability and low maintenance needs in most environments.Corten B Grades & Equivalents Grades:
| Corten | EN 10025-5:2004 |
| Corten B | S355J2W |
Corten B Mechanical Properties
| Grade | Thickness (mm) Strip Products | Plate Products | Yield Strength Rel N/mm² Minimum | Tensile Strength Rm N/mm² Minimum | Elongation A50 % Minimum |
| Corten B | 2-13 | 6-40 | 345 | 485 | 19 |
Corten B Steel Chemical Composition
| C | 0.19 |
| Si | 0.30/0.65 |
| Mn | 0.80/1.25 |
| P | 0.035 |
| S | 0.03 |
| Al | 0.020/0.06 |
| V | 0.02/0.10 |
| Cu | 0.25/0.40 |
| Cr | 0.40/0.65 |
| Ni | 0.4 |
Corten Steel Uses
Corten weathering steel is used for outdoor projects and art because it forms a rust layer that gives it a unique, weathered look. It’s great for sculptures, bridges, and garden walls, adding a rustic touch while being durable. Corten steel is also used for bike racks, tree grilles, and planters, making it a versatile choice for public spaces. Its strength and low maintenance make it suitable for marine transport, container construction, and sheet piling.
Read More Our Blog – Why To Use Weathering Steel
Benefits of Weathering Steels
Wide Range of Uses: Weathering steel resists rust and is great for structures like bridges, buildings, towers, and sculptures. It also handles high temperatures well, making it suitable for flues, chimneys, and ducts.Practical Advantages:
- Low Maintenance: Weathering steel needs very little upkeep. It’s ideal for hard-to-reach structures like bridges where maintenance would be difficult.
- Cost Savings: You save on the cost of paint, which can make weathering steel cheaper overall. For instance, it can be about 5% cheaper than painted steel for bridges.
- Long-Term Savings: Less maintenance means lower costs and fewer disruptions, like traffic delays.
- Faster Construction: Skipping the painting step speeds up the building process.
- Attractive Appearance: Over time, weathering steel develops a rust-like patina that looks good and blends with natural surroundings.
- Environmental Benefits: No need for paint means fewer concerns about harmful chemicals and waste.
- Safety: Avoids the risks of painting and reduces maintenance-related safety issues.
- High-Temperature Performance: Weathering steel handles temperatures above 400°C well, forming a protective layer even without water.
Conclusion: Selecting the Right Corten Steel for Your Project
Corten steel offers a range of types and grades that meet various needs in construction, architecture, and art. Choosing the right material for your project requires an understanding of each type’s unique properties.
- Corten A: Ideal for aesthetic facades and gas flue applications, this grade provides self-protecting qualities and is cost-effective. However, it is not recommended for heavy load-bearing structures.
- Corten B: Designed for heavy and load-bearing structures, Corten B forms its own protective layer but may require regular painting in persistently wet conditions.
When selecting the appropriate Corten steel grade, consider factors like structural needs, environmental conditions, maintenance requirements, and aesthetic goals. Consulting with steel suppliers and experts can help ensure your project’s success.Explore the potential of Corten Steel with Lakshya Steel to create durable, visually appealing, and sustainable structures.
