What is the carbon content range for low carbon steel?

• A. 0.05-0.30%
• B. 0.15-0.30%
• C. 0.30-0.45%
• D. 0.75-1.50%

Answer: (A)

Carbon content is the main factor that defines steel categories and how it behaves in welding and forming. Low carbon steel, or mild steel, has only a small amount of carbon, which keeps it very formable and easy to weld. The usual range for low carbon steel is about 0.05% to 0.30% carbon by weight. This combination gives good ductility and weldability while keeping strength reasonably modest.

So, the range 0.05–0.30% matches this commonly cited span for low carbon steel. The other ranges point to higher carbon content: 0.30–0.45% is typically medium carbon, and 0.75–1.50% is high carbon, which are stronger but harder to weld.