1. According to the mass percentage of carbon: low carbon steel (C:≤0.25%); medium carbon steel (C:0.25≤C≤0.6%); high carbon steel (C:>0.6%)
2. According to the quality of steel (mainly the content of impurities sulfur and phosphorus):
Ordinary carbon steel (S≤0.055%, P≤0.045%)
High-quality carbon steel (S≤0.040%, P≤0.040%)
High quality carbon steel (S≤0.030%, P≤0.035%)
3. By use:
Carbon structural steel: mainly used for bridges, ships, building components, machine parts, etc.;
Carbon tool steel: mainly used for tools, molds, measuring tools, etc.;