Carbon steel is the carbon content in 0.0218% to 2.11% of iron carbon alloy also called carbon steel generally also contains a small amount of silicon manganese sulfur phosphorus carbon steel in the higher the carbon content is the greater the hardness, the higher the strength, but the lower the plasticity
 
Classify
(1) according to the use of carbon steel can be divided into carbon structural steel carbon tool steel and free cutting structural steel three types, carbon structural steel is divided into engineering construction steel and machine manufacturing structural steel two kinds; 
(2) according to smelting method, it can be divided into open hearth steel and converter steel; 
(3) According to the deoxidation method can be divided into boiling steel (F) killed steel (Z) semi-killed steel (B) and special killed steel (TZ); 
(4) according to carbon content, carbon steel can be divided into low carbon steel (WC0.25%), 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 (phosphorus and sulfur higher) high quality carbon steel (phosphorus and sulfur lower) and high quality steel (phosphorus and sulfur lower) and super grade high quality steel folding.

The influencing factor
1.manganese
is about 0.25%~0.80% solution strengthening. Remove FeO and reduce the brittleness of steel; MnS synthesized with sulfurization can reduce the harmful effect of sulfur .2.silicon
is about 0.10%~0.40%. In addition to the adverse effect of FeO on steel quality, the beneficial.
3.sulfur
FeS and Fe form eutectic with low melting point (melting point is 985), which causes steel to become brittle and crack during hot processing from 1000 to 1250. "hot brittleness" is harmful to.
4.phosphorus
strength and hardness, but reduces plasticity and toughness, and "cold brittleness" is harmful.

A572GR is divided into five grades: grade 42, grade 50, Grade 55 for riveting, bolted or welded structural parts; Grade 60 and 65 for riveting and bolted structural parts for bridge or other purposes.

Mechnical property 

Chemical composition 

Mechanical Property

Chemical Component