Steel is the backbone of modern industries, used in construction, automotive, manufacturing, oil & gas, and engineering. The versatility of steel largely comes from its carbon content, which directly affects strength, ductility, hardness, and weldability.

Depending on carbon percentage, steel is generally classified into three categories:

• Low Carbon Steel (Mild Steel) → Up to 0.25% carbon
• Medium Carbon Steel → 0.30% – 0.60% carbon
• High Carbon Steel → 0.60% – 2.0% carbon

What is Low Carbon Steel (Mild Steel)?

Low Carbon Steel, also known as Mild Steel, contains 0.05% – 0.25% carbon. It is the most widely used steel type due to its affordability, high ductility, and excellent weldability.

Key Properties:

• Carbon Content: 0.05 – 0.25%
• Tensile Strength: 250 – 400 MPa
• Hardness: ~120 – 160 HB
• High ductility and machinability
• Poor corrosion resistance (needs galvanizing or painting)

Common Grades:

• AISI 1008 / 1010 / 1018
• EN32 / S235JR
• DIN C15 / C22

Explore our Engineering Steel for mild steel options used in structural and fabrication works.

Applications:

• Construction (beams, columns, reinforcement bars)
• Automotive body panels
• Pipes, tubes, and pipelines
• General fabrication and welding

What is Medium Carbon Steel?

Medium Carbon Steel contains 0.30% – 0.60% carbon, offering a balance between strength and ductility. It is stronger than mild steel but still workable.

Key Properties:

• Carbon Content: 0.30 – 0.60%
• Tensile Strength: 600 – 850 MPa
• Hardness: ~170 – 250 HB
• Moderate ductility and machinability
• Can be heat-treated for improved wear resistance
• Weldability is lower than mild steel

Common Grades:

• AISI 1030, 1040, 1045 (C45)
• EN8 (080M40)
• DIN C40, C45, C55

Learn more about our C45 Carbon Steel, a widely used medium carbon steel grade in engineering applications.

Applications:

• Shafts, axles, and gears
• Automotive components
• Forgings, crankshafts, and machine parts
• Rail tracks and engineering tools

What is High Carbon Steel?

High Carbon Steel contains 0.60% – 2.0% carbon, making it extremely hard, strong, and wear-resistant, but also more brittle and difficult to weld.

Key Properties:

• Carbon Content: 0.60 – 2.0%
• Tensile Strength: 900 – 1200 MPa
• Hardness: ~200 – 650 HB (after heat treatment)
• Very high hardness and wear resistance
• Very low ductility and toughness
• Requires special welding techniques

Common Grades:

• AISI 1060, 1080, 1095
• EN9 (070M55), EN31
• DIN C60, C75, C105W1

Check our Tool Steel range for high-carbon steels used in tools and wear parts.

Applications:

• Cutting tools, blades, and knives
• Springs and wires
• High-strength wear components
• Dies, hand tools, and bearings

Comparison: Carbon Content, Mechanical Properties & Hardness

The following table highlights the differences between low, medium, and high carbon steels:

Advantages & Disadvantages

Examples of Carbon Steel Grades

For higher strength, explore our EN19T Alloy Steel, a toughened carbon-alloy grade for engineering use.

Which One Should You Choose?

• Low Carbon Steel (Mild Steel): Best for construction, pipelines, and automotive panels where weldability and cost matter.
   
• Medium Carbon Steel: Suitable for gears, axles, shafts, and forgings where strength and toughness are important.

High Carbon Steel: Ideal for cutting tools, blades, and springs where hardness and wear resistance are critical.

Conclusion

The choice between low carbon (mild steel), medium carbon, and high carbon steels depends on your project requirements.

• Mild steel offers ductility, weldability, and cost-effectiveness.
• Medium carbon steel balances strength and toughness.
• High carbon steel provides hardness and wear resistance for specialized applications.

At Nifty Alloys LLC, we supply a complete range of carbon steels, alloy steels, tool steels, and engineering steels across the UAE and worldwide. All products come with mill test certificates (MTCs) to ensure global quality compliance.