A Key Material in Industry
Carbon steel, often referred to as plain carbon steel, is a fundamental material widely used across various industries. It is primarily an alloy of iron and carbon, with the total alloying elements kept below 2% by mass. The specific limits for elements are 0.6% for copper, 1.65% for manganese, 0.04% for phosphorus, 0.6% for silicon, and 0.05% for sulfur. Notably, carbon steel does not include additional elements to enhance particular properties.
Baoalloy : Your Go-To Carbon Steel Distributor
Baoalloy supplies a comprehensive range of carbon steel products, including:
- Bars
- Pipes and Tubes
- Plates
- Sheets
- Structural Components
- Grating
- Expanded Metal
- And more
Factors to Consider When Choosing Carbon Steel
When selecting carbon steel, it’s important to understand the three primary categories based on carbon content. Higher carbon levels generally increase the material’s hardness and strength. For example, low carbon steel (0.06% to 0.25%) is versatile and easily shaped, whereas high carbon steel (above 0.55%) offers enhanced strength but less flexibility.
- Low Carbon Steel: 0.06% to 0.25% carbon (mild)
- Medium Carbon Steel: 0.25% to 0.55% carbon (moderate strength)
- High Carbon Steel: Over 0.55% to 1.00% carbon (high strength)
Carbon Steel Grade Classification
The carbon steel grades are classified into different series:
- 10XX Series: Non-resulpherized carbon steel, maximum manganese content of 1.00% (e.g., 1018, 1045).
- 11XX Series: Resulpherized carbon steel (e.g., 1117, 1141).
- 12XX Series: Rephosphorized and resulpherized carbon steel (e.g., 12L14).
The last two digits in the AISI-SAE designation indicate the approximate carbon content, such as in 1018 where the carbon content ranges from 0.15% to 0.20%.
Key Properties of Carbon Steel
According to the American Iron and Steel Institute (AISI), carbon steel is characterized by the absence of specified minimum contents for various alloying elements like chromium and nickel. The limits for manganese, silicon, and copper are also defined, ensuring that the steel remains within carbon steel specifications.
The carbon content significantly influences the mechanical properties of carbon steel. Increased carbon levels lead to higher hardness and strength, making lower carbon steel more workable through processes like bending and welding. Conversely, higher carbon steels are favored for applications requiring exceptional durability, such as in manufacturing cutting tools.
As carbon content rises, the potential for heat treatment to enhance hardness increases, although this may compromise ductility. Furthermore, higher carbon content can negatively impact weldability and reduce the melting point of the steel.