Carbon Steel

Carbon steel is an iron-carbon alloy with a carbon content of 0.0218% to 2.11%. Also called carbon steel. Generally, it also contains a small amount of Si, Mn, S, and P. Generally, the higher the carbon content in carbon steel, the greater the hardness and the higher the strength, but the lower the plasticity.

1. According to the application, carbon steel can be divided into three types: carbon structural steel, carbon tool steel and free-cutting structural steel. Carbon structural steel is further divided into engineering construction steel and machine manufacturing structural steel.

2. According to the smelting method, it can be divided into open-hearth steel and converter steel.

3. According to the deoxidation method, it can be divided into boiling steel (F), killed steel (Z), semi-killed steel (b) and special killed steel (TZ).

4. According to the carbon content, carbon steel can be divided into low carbon steel (WC ≤ 0.25%), medium carbon steel (WC0.25%—0.6%) and high carbon steel (WC>0.6%).

5. According to the quality of steel, carbon steel can be divided into ordinary carbon steel (higher in P and S), high-quality carbon steel (lower in P and S) and advanced high-quality steel (lower in P and S) and premium quality steel.

Carbon structural steel

0.05 to 0.15% carbon (plain carbon steel) content.

Features: low price, excellent process performance (such as weldability and cold formability).

Application: general engineering structures and general mechanical parts. For example, Q235 can be used to make bolts, nuts, pins, hooks and less important mechanical parts, as well as rebar, section steel and steel bars in building structures.

Carbon tool steel

Approximately 0.6 to 1.0% carbon content.

Features: It belongs to eutectoid steel and hypereutectoid steel, with high strength and hardness and good wear resistance, suitable for manufacturing various low-speed cutting tools.

Application: very strong for springs, knives and high strength wires, sledgehammers, punches, chisels, woodworking tools, scissors.

Free-cutting structural steel

Approximately 0.3–0.5% carbon content.

Features: Balance ductility and strength, has good wear resistance, contains a small amount of easy-cutting elements, and has good cutting performance.

Application: suitable for the manufacture of more important machine structural parts, such as machine tool gear shafts, spline shafts, tractor drive shafts, or for large parts, forging and automotive parts, etc.