Carbon Steel 500N is a non-alloy high-strength structural steel, where the "500" denotes its minimum yield strength of 500 N/mm² (or 500 MPa). Combining high strength, good toughness, and excellent machinability, this steel is widely used in structures that bear significant loads, such as buildings, machinery, and bridges.

2.Performance of Carbon Steel 500N

The performance of Carbon Steel 500N is primarily determined by its carbon content and trace alloying elements. Below are its typical performance parameters:

• Yield Strength (MPa): ≥500

• Tensile Strength (MPa): 550–650

• Hardness (HB): 150–220

• Elongation (%): 15–25

• Impact Toughness (J, at room temperature): Good

• Weldability: Moderate

• Machinability: Good

3.Main Chemical Composition (Typical Values)

The chemical composition of Carbon Steel 500N determines its strength, toughness, and weldability:

• Carbon (C): 0.20–0.35% – affects strength and hardness

• Silicon (Si): 0.15–0.40% – enhances strength and oxidation resistance

• Manganese (Mn): 0.60–1.20% – improves hardenability and wear resistance, aiding weldability

• Phosphorus (P): ≤0.030%

• Sulfur (S): ≤0.030% – kept at low levels to maintain toughness and weldability

4.Common Applications of Carbon Steel 500N

Due to its high strength, excellent toughness, and good machinability, Carbon Steel 500N is widely used in the following industries:

• Construction: Bridges, high-rise buildings, steel structural frameworks

• Machinery Manufacturing: Construction machinery, agricultural machinery, automotive components

• Pressure Vessels: Storage tanks, pipelines, boilers

• Shipbuilding: Hull structures, offshore platforms

5.Welding and Machining of Carbon Steel 500N

（1）Weldability

Carbon Steel 500N has moderate weldability and requires appropriate welding techniques to reduce the risk of cracking：

• Low-hydrogen electrodes are recommended to minimize cold cracking risks.

• For thick plates, preheating to 150–250°C and slow cooling post-weld help reduce stress concentration.

• Post-weld heat treatment (tempering) can further improve toughness, typically within 500–650°C.

（2）Machining Performance

Carbon Steel 500N exhibits excellent cutting performance and can be processed using conventional machining methods:

• Suitable for turning, milling, drilling, and other operations.

• Carbide cutting tools improve efficiency and tool life.

• The use of cutting fluids helps reduce heat buildup and enhances machining quality.

6.Heat Treatment

Carbon Steel 500N is typically subjected to normalizing to refine its microstructure and optimize performance:

• Heating Temperature: 850–900°C

• Soaking Time: 1 hour per 25mm thickness

• Cooling Method: Air cooling to room temperature

7.Standards and Equivalent Grades

Different countries and regions classify Carbon Steel 500N under various standards and grades:

• China：GB Q500

• USA：ASTM A572 Gr.65

• Europe：EN S500MC

• Japan：JIS SM490Y

8.Advantages of Carbon Steel 500N

• High Strength – Yield strength of ≥500 MPa, capable of handling high loads.

• Excellent Toughness – Maintains stable performance under impact loads.

• Good Machinability – Suitable for conventional cutting, welding, and forming processes.

• Cost-Effective – More economical compared to high-alloy steels while maintaining superior performance.

9.Key Considerations

• Preheating and post-treatment – Necessary for reducing stress concentration during welding.

• Corrosion Protection – Coating or galvanization is recommended in corrosive environments.

• Proper Storage – Avoid moisture and oxidation to maintain optimal material properties.

10.Conclusion

With its high strength, excellent machinability, and cost-effectiveness, Carbon Steel 500N finds extensive applications in construction, machinery, bridges, and shipbuilding. By employing appropriate welding and heat treatment techniques, its performance can be further optimized, ensuring outstanding performance even in demanding conditions. When selecting and using Carbon Steel 500N, careful consideration of standards, processing methods, and protective measures is essential to maximize its potential.

We can process this alloy into round bars, plates, round pipes/square pipes, and coils according to your requirements. If you have any inquiries, please feel free to contact us. Our email address is: sale@bolaibao1.com. We look forward to your inquiry!