Carbon steel, commonly referred to as ordinary carbon structural steel, has a carbon content of less than 0.38%, with less than 0.25% being the most commonly used. It falls under low carbon steel, and when the thickness is less than 16 mm, each metal grade represents the yield point of the steel.

Carbon steel is a short name for common carbon structural steel. With a carbon content less than 0.38%, the one below 0.25% is commonly used. It falls under low-carbon steel, with each metal grade indicating the low yield point of the steel when the thickness is less than 16 mm. Compared to carbon steel, it has a broader range of limitations on carbon content, performance range, residual elements like phosphorus and sulfur. According to the guaranteed delivery conditions, common carbon steel in our country and some other nations is categorized into three types: Grade A steel (Grade A steel), which guarantees only mechanical properties, not chemical composition; Grade B steel (Grade B steel), which guarantees only chemical composition, not mechanical properties; and Special steel (Grade C steel), which guarantees both chemical and mechanical properties. Special steel is often used to manufacture important structural components.

Carbon structural steel is primarily used for manufacturing engineering components. It is generally used in the supplied state, with higher sulfur and phosphorus contents in the steel, reaching up to 0.050% and 0.045% respectively. This type of steel accounts for a significant portion of the total steel production.