Carbon steel types

Carbon steel types
Carbon steel can be divided into various types according to different classification standards:

Classification according to carbon content:

Low carbon steel: The carbon content is less than 0.25%. It has good plasticity and toughness and is easy to process. It is often used to make chains, rivets, bolts, etc.
Medium carbon steel: The carbon content is between 0.25% and 0.6%, and its strength and hardness are higher than low carbon steel. It is used to manufacture moving parts such as axles, worms, and gears.
High carbon steel: with a carbon content of more than 0.6%, high strength and hardness, but poor weldability and plasticity, it is used to make springs, wear-resistant parts and cutting tools.
Classification according to use:

Carbon structural steel: Mainly used in the manufacture of structural parts and machine parts, usually medium carbon steel and low carbon steel.
Carbon tool steel: Mainly used to make knives, measuring tools and molds, usually high carbon steel.
Classification according to quality:

Ordinary carbon steel: contains higher impurities such as sulfur and phosphorus, lower cost, and strong processability.
High-quality carbon steel: lower impurity sulfur and phosphorus content, better quality.
High-grade high-quality steel: the lowest content of impurities sulfur and phosphorus, the highest quality.
Classification of tissue according to room temperature equilibrium:

Hypoeutectoid steel: Steel with a lower carbon content than the eutectoid composition.
Eutectoid steel: Steel with a carbon content equal to the eutectoid composition.
Hypereutectoid steel: Steel with a carbon content higher than the eutectoid composition.
Other types:

Alloy carbon steel: Contains other elements such as molybdenum, chromium, nickel, etc. to improve mechanical properties, corrosion resistance and heat resistance.
Special carbon steel: has specific uses, such as spring steel, mechanical flange steel, bearing steel, etc., and has special organizational structure and mechanical properties.