Carbon steel bar is a solid long strip of steel, the common ones are round steel, square steel, hexagonal steel, octagonal steel and so on. Round steel is often used to make steel bars, bolts and various mechanical parts, as well as tube blanks for seamless steel pipes.

According to the process, round steel is divided into three types: hot-rolled round steel, forged round steel and cold-drawn round steel. According to chemical composition (that is, carbon content), it can be divided into low carbon steel round steel, medium carbon steel round steel and high carbon steel round steel. According to the quality of steel, it can be divided into ordinary carbon steel round bar and high-quality carbon steel round bar. According to the application, it can be divided into carbon structural steel and carbon tool steel.

Square steel refers to steel rolled or processed into a square cross-section, which can be divided into hot-rolled and cold-rolled.

Classification of carbon steel:

According to the application, carbon steel can be divided into three categories: carbon structural steel, carbon tool steel and free-cutting structural steel. Carbon structural steel can be divided into building structural steel and machine-made structural steel. According to the carbon content, carbon steel can be divided into low carbon steel (ωc≤0.25%), medium carbon steel (ωc=0.25%-0.6%) and high carbon steel (ωc>0.6%)

According to the amount of phosphorus and sulfur, carbon steel can be divided into ordinary carbon steel (higher phosphorus and sulfur), high-quality carbon steel (lower phosphorus and sulfur) and advanced high-quality steel (lower phosphorus and sulfur) Generally, the higher the carbon content in carbon steel, the higher the hardness and the higher the strength, but the lower the plasticity.

08-25 steel has low carbon content, low strength and hardness, good plasticity, toughness and weldability. It is mainly used to manufacture stamping parts, welded structural parts and mechanical parts with low strength requirements.

30-55 belongs to quenched and tempered steel, which has good comprehensive mechanical properties after being quenched and tempered, and is mainly used to manufacture mechanical parts with greater stress.

The steel above 60 belongs to spring steel, which can obtain a higher elastic limit after heat treatment, and is mainly used for the manufacture of elastic parts.

The difference between round steel and other steel bars

1. The appearance is different, the round steel has a smooth appearance, no texture and no ribs, and other steel bars have engraved or ribbed surface appearance, which causes the bonding force between the round steel and the concrete to be small, while the other steel bars and the concrete have less adhesion. Great adhesion.

2. The composition is different. Round steel (grade 1 steel) belongs to ordinary low carbon steel, and other steel bars are mostly alloy steel.

3. The strength is different, the strength of the round steel is low, and the strength of other steels is high, that is, the round steel with the same diameter can withstand less tensile force than other steel bars, but the plasticity of the round steel is higher than that of other steel bars. Strong, that is, the round steel has a large deformation before being broken, while the deformation of other steel bars is much smaller before being broken.