25mm Width x 5mm Thick Flat Mild Steel Bar Section

Mild Steel Bar

Our flat mild steel bar is 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 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.

With a 25mm width and 5mm thickness, Speciality Metals offers durable and versatile mild steel bars. This bar section is available in various lengths and is well known for its excellent welding, forming, bending and machining capabilities. Its malleability and recyclability make mild steel flat bars a cost-effective product in many applications. Whether you are fabricating structural components or creating ornamental designs, you can use this flat mild steel bar section. Its versatility allows it to be used in a wide range of industries, such as construction, manufacturing, and home improvement. Trust in Speciality Metals’ expertise and rely on their high-quality products for all your flat bar needs.

Key information:

• Width – 25mm
• 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.

What’s the Difference Between Hot Rolled and Cold Rolled Mild Steel Bar?

Hot rolled and cold rolled are two primary methods used in the production of mild steel bars, and they result in distinct properties and applications for the steel. 

1. Manufacturing Process:

   • Hot Rolled: The steel is heated above its recrystallisation temperature (typically over 1,000°F) and then passed through rollers while still hot, giving it its shape. This process often results in a scaled surface due to oxidation.
   • Cold Rolled: The steel is rolled at room temperature, below its recrystallisation point, which leads to increased strength and hardness. Before this process, the steel is usually cleaned to remove any scale, resulting in a smoother finish.

2. Appearance:

   • Hot Rolled: It generally has a rough and scaled surface, which gives it a slightly mottled appearance.
   • Cold Rolled: It has a smoother, more polished appearance without the scale that hot rolled steel often has.

3. Tolerance:

   • Hot Rolled: This process typically results in less precise tolerances than cold rolling. The material might slightly shrink as it cools, leading to size variations.
   • Cold Rolled: Cold rolled steel generally has tighter dimensional tolerances and a more consistent cross-sectional area.

4. Strength & Hardness:

   • Hot Rolled: It has a lower tensile strength and is easier to form than cold rolled steel.
   • Cold Rolled: The cold rolling process increases the steel’s tensile strength and hardness. This is due to the strain introduced into the crystal structure of the steel during the rolling process.

5. Applications:

   • Hot Rolled: Given its softer and more ductile nature, it’s typically used for structural projects like beams, tracks and construction.
   • Cold Rolled: Due to its higher strength and tighter tolerances, it’s used in applications that require precision, such as appliance manufacturing, automotive parts and even some types of electronics.

6. Price:

   • Hot Rolled: Generally, it is less expensive than cold rolled steel because it’s easier to produce and doesn’t require the additional processing that cold rolled steel does.
   • Cold Rolled: Typically, it’s more expensive than hot rolled steel due to the extra processing steps and its higher quality finish.

Can Mild Steel Bars be Recycled?

Absolutely, mild steel bars can be recycled. Mild steel, like other forms of steel, is part of one of the world’s most recycled materials. When these bars reach the end of their lifecycle or are left as scrap from various projects, they can be collected and returned to steel mills or recycling facilities. There, they are melted down and repurposed into new steel products, including new mild steel bars. The recycling process involves shredding the steel into smaller pieces, separating impurities and then melting it in a furnace to produce new steel. This recycling loop can be repeated numerous times without significant degradation in the quality of the steel. Recycling not only conserves resources and energy but also reduces the need for mining new iron ore, which, in turn, reduces environmental impacts. Given the efficiency and sustainability benefits of recycling, many industries and governments actively promote the recycling of mild steel and other metals.

How can I Prevent Warping of Mild Steel Flat Bars During Welding?

Warping or distortion of mild steel flat bars during welding is a common challenge, caused by the expansion and contraction of the material as it heats up and cools down. However, by taking preventive measures and using the right techniques, you can minimise or eliminate this issue.

1. Preparation:

   • Clean the Material: Ensure the steel bar is clean from rust, paint, oils or other contaminants. Clean surfaces lead to better welds and less heat input.
   • Edge Preparation: If you’re doing a full penetration weld, preparing the edges (like beveling) can reduce the amount of filler metal needed, reducing the total heat input.

2. Tack Welds:

   • Before completing the full weld, use tack welds at intervals along the joint. This helps to hold the material in place and counteracts the forces of contraction and expansion.

3. Stitch Welding:

   • Instead of running a continuous weld, use short, staggered welds (or stitch welds). This method spreads the heat over a more extensive area, reducing localised expansion and contraction.

4. Clamping and Jigs:

   • Use clamps or jigs to hold the flat bar in place during welding. This can resist the forces causing warping.

5. Welding Sequence:

   • Plan your welding sequence to counteract distortion. If welding on opposite sides of a piece, alternate sides to balance the heat input.

6. Heat Control:

   • Use the lowest effective welding amperage to minimise the heat input.
   • Employ a welding technique that allows the base metal to cool between passes, like backstepping.
   • Use a weaving technique, but ensure it’s not too wide as that can introduce more heat.

7. Interpass Temperature:

   • Monitor the temperature between welding passes. Allow the material to cool down to a manageable interpass temperature before starting the next pass.

8. Peening:

   • Gently hammering the weld while it’s still hot (peening) can help counteract the forces of contraction. However, it’s essential to avoid over-peening, which can cause its own set of problems.

9. Preheating:

   • Preheating the steel can make the cooling process slower and more controlled, reducing the chances of warping. It’s especially useful for thicker materials.

10. Post-weld Heat Treatment:

• After welding, controlled heating and cooling (post-weld heat treatment) can help relieve stresses in the welded area, reducing the risk of distortion.