A Guide To Weathering Steel Plates

Weathering or corten steel plates are popular among construction industry professionals due to their unique properties. These plates are designed to weather over time, forming a protective layer of rust that protects the steel beneath. Weathering steel is highly durable and low maintenance, making it an excellent choice for many projects. However, some important factors should be considered before weathering steel plates. In this guide, we’ll take a closer look at some of the key characteristics of this type of steel, along with some tips on how to use it effectively.

What Are Weathering Steel Plates?

Weathering steel plates, also known as corten steel, are high-strength, low-alloy (HSLA) steel designed to form a protective rust-like coating on its surface when exposed to the elements. This process, called patina formation, gives Weathering Steel Plates its unique orange-brown colour and serves as a natural barrier against corrosion. These plates are commonly used in outdoor structures such as bridges and buildings for their durability and aesthetic appeal. Weathering steel comprises iron, chromium, copper, and nickel, which work together to create this self-protective layer.

Understanding The Properties Of Weathering Steel

Weathering steel is a high-strength, low-alloy metal designed to resist corrosion and rust without requiring a coating or protective layer. This unique quality is achieved through a process known as “patination” – the development of a natural, protective layer of rust on the surface of the steel. This layer prevents moisture and oxygen from reaching the underlying steel, preventing further corrosion and allowing the material to retain its structure and strength over time. Weathering steel, such as bridges, buildings, and outdoor sculptures, is typically used when corrosion resistance is a priority.

Choosing The Right Grade And Thickness

When selecting weathering steel for a particular project, it’s important to consider the application’s specific requirements. Weathering steel comes in various grades and thicknesses, each with unique properties and strengths. Some grades are designed to withstand extreme temperatures or harsh weather conditions, while others are more suited to indoor or less challenging environments. The thickness of the steel is also an important consideration, as thicker steel will generally be more durable and resistant to wear and tear.

Proper Maintenance And Care

Although weathering steel is highly durable, it requires proper care and maintenance to ensure longevity. Regular cleaning and inspection can help prevent any debris or organic matter buildup that can lead to corrosion or rust. If rust does occur, it’s important to address it properly by using a wire brush or sandpaper to remove any loose rust and applying a rust converter or inhibitor to prevent further corrosion. It’s also important to avoid using salt or other corrosive substances near weathering steel, as this can accelerate the corrosion process and compromise the metal’s integrity.

Considerations When Welding Weathering Steel

Welding weathering steel requires special considerations due to the unique characteristics of the metal. First and foremost, it’s important to select a welding electrode designed specifically for weathering steel to ensure proper bonding and prevent excessive corrosion. The welding process should also be closely monitored to ensure the correct temperature and heat input are maintained. It’s also a good idea to avoid welding weathering steel in high humidity or excessively wet conditions, as this can lead to excessive corrosion and weakening of the metal.

Applications For Weathering Steel

Weathering steel is ideal for many applications thanks to its high structural integrity and corrosion resistance. Some common uses include bridges, major infrastructure projects, building facades, and outdoor sculptures and artwork. Weathering steel is also becoming an increasingly popular choice for residential construction, particularly in areas with harsh weather conditions or high humidity. The unique patina that forms on the surface of the steel adds a distinct aesthetic quality that can help enhance the look and feel of any project.


Weathering steel is a versatile and effective material that can help ensure lasting durability and performance. Whether you’re looking to build a bridge, create an outdoor sculpture, or construct a residential building, weathering steel can help meet your needs easily. By understanding the unique characteristics of this metal and following proper maintenance and care procedures, you can help ensure that your weathering steel plates will continue to perform at the highest level for years to