20mm Width x 5mm Thick Mild Steel Section Flat Metal Bars

Flat Metal Bars

Our mild steel flat metal bars are available in S275 grade. Engineers and contractors use flat bar extensively in the manufacture of support braces, latches, mechanical parts, industrial tools, etc., as well as for many DIY projects.

For those in need of sturdy and reliable steel material, the mild steel flat bar offers a versatile solution. As a popular choice in the construction and manufacturing industries, this steel strip provides a solid foundation for various structures and machinery. With its uniform width and thickness, the mild steel flat bar offers consistent strength and durability for a wide range of applications.

As a result of its good to excellent formability, mild steel flat bar can easily be joined by welding processes or by means of fixings such as rivets, bolts and screws.

Have you heard about these flat metal bars by Speciality Metals? Made from durable mild steel, they’re 20mm wide and 5mm thick, and come in a variety of lengths – perfect for any project! Not only are they cost-effective, but they’re also extremely versatile. These bars have great welding, forming, bending and machining abilities, making them an excellent choice for any metalworking project. And the best part? They’re recyclable and malleable, so you can feel good about your purchase while also creating something beautiful. Check out these flat metal bars for your next project and see just how high quality they really are.

Key information:

• Width – 20mm
• Thickness – 5mm
• Shape – Flat
• Grade –S275
• Finish – Mill

Speciality Metals are the best suppliers for you because:

• FREE UK delivery on all orders
• Order dispatch within 24 hours of order
• Located in Warrington, UK which is the UK home of mesh and metals
• Our experienced staff are experts in the mesh market and care personally about your customer experience

We also carry a wide range of mild steel sheet metal, angle iron and round tube.

How Does Weathering Affect Mild Steel Flat Bars?

Weathering, or the exposure of materials to the natural environment, has a pronounced effect on mild steel flat bars. Mild steel, primarily composed of iron, is particularly susceptible to the effects of moisture, oxygen and other environmental factors. The most common result of weathering on mild steel is the formation of iron oxide, commonly known as rust.

When mild steel flat bars are left unprotected in an open environment, they begin to react with the oxygen in the presence of moisture, initiating the corrosion process. Over time, a reddish-brown layer of rust forms on the surface, which can flake off and expose the underlying metal to further oxidation. This process can gradually reduce the thickness and strength of the steel if not addressed.

Apart from moisture and oxygen, other factors like industrial pollutants, salt (especially in marine environments), and acidic rain can accelerate the corrosion process. In areas with high humidity or proximity to the sea, the rate of rusting can be considerably faster.

However, this characteristic of mild steel has also been employed artistically and architecturally. The development of weathering steel, often referred to by the brand name “Corten,” takes advantage of this natural rusting process. When exposed to the elements, weathering steel forms a stable, protective rust layer that prevents further corrosion and gives structures a distinct, rustic appearance.

Is Mild Steel Flat Bar Suitable for High-Strength Applications?

Mild steel flat bars, while versatile and widely used in various applications, are not typically the first choice for high-strength applications.

1. Composition & Properties: Mild steel, often referred to as carbon steel, generally has a lower carbon content (usually around 0.05% to 0.25%) compared to high carbon or alloy steels. This low carbon content provides mild steel with its characteristic malleability and ductility, but it also means that it doesn’t have the same tensile strength as higher carbon steels.

2. Yield Strength: The yield strength of mild steel – the point at which it undergoes permanent deformation when under stress – is lower than that of high-strength steels. This makes it less suitable for applications that demand high resistance to stress or load.

3. Hardening: While mild steel can be case-hardened to improve its surface strength, its core remains relatively soft, making it unsuitable for applications where through-hardening is required.

4. Applications: Mild steel flat bars are commonly used in construction, automotive bodywork, gate and fence fabrication and other general-purpose projects where high strength is not the primary concern. In contrast, high-strength applications, such as heavy-duty machinery, bridges or certain parts of automotive structures, typically require steels with higher carbon content or alloying elements that enhance strength.

5. Alternatives: For high-strength applications, alternatives to mild steel include high-strength low-alloy (HSLA) steels, stainless steels or tempered and quenched steels. These materials offer superior tensile and yield strengths, making them more suitable for demanding applications.

Can Mild Steel Flat Bar be Hardened?

Mild steel flat bar can be hardened to a certain extent, but it will not achieve the same level of hardness as high-carbon or alloy steels. The method commonly used to harden mild steel is called “case hardening” or “surface hardening.”

Case Hardening of Mild Steel Flat Bar:

1. Carbon Enrichment: The primary principle behind case hardening is to increase the carbon content of the outer layer of the mild steel. This is achieved by exposing the steel to a carbon-rich environment at high temperatures.

2. Carburizing: One of the common case hardening methods involves carburising, where the mild steel is heated in the presence of a carbon-rich substance, such as charcoal or carbon monoxide. This allows carbon atoms to diffuse into the steel surface.

3. Quenching: After carburizing, the steel is rapidly cooled or quenched in water, oil or another quenching medium. This rapid cooling traps the carbon within the steel’s surface, leading to the formation of a hard layer of martensite.

4. Result: The outcome of case hardening is a mild steel flat bar with a tough and wear-resistant outer layer (or “case”) while retaining a softer, ductile core. This combination provides improved wear resistance on the surface while maintaining the overall toughness and shock-absorbing properties of the core.

5. Limitations: While case hardening does enhance the hardness of mild steel’s surface, it doesn’t produce the deep, through-hardening that can be achieved with high-carbon or alloy steels. This means that if the hardened surface wears down or is significantly machined, the softer, untreated core will be exposed.