Carbon structure steel is a kind of mild steel, the carbon content is less than 0.25%. It has a relatively low strength and ductility, but it can be easily formed, machined and welded. Carbon structure steel is widely used in many fields, like as construction, locomotive, machinery and ships.
Carbon structure steel typically has a chemical composition of 0.05-0.30% Carbon and Mn 0.60-1.65%. In order to improve its formability, some manufacturers add manganese, silicon, nickel or vanadium to the steel.
There are many types of carbon structure steel, and each type has its own grade and designation. Here are some common grades of carbon structure steel with their designations and chemical compositions.
1. High carbon structure steel
Designation: SS400, S20C
Chemical Composition: C 0.25-0.45% and Mn 0.60-0.90%
2. Low carbon structure steel
Designation: SAE1006, SAE1008
Chemical Composition: C 0.10-0.25% and Mn 0.50-0.80%
3. Medium carbon structure steel
Designation: CG20, S35C
Chemical Composition: C 0.30-0.45% and Mn 0.60-0.90%
4. High strength low alloy structure steel
Designation: SR45, SR50
Chemical Composition: C 0.15-0.20% and Mn 0.90-1.25%
5. Hot-rolled structure steel
Designation: SS400, SAE1020
Chemical Composition: C 0.15-0.30% and Mn 0.90-1.25%
6. Cold-rolled structure steel
Designation: SAE1010, SPCC
Chemical Composition: C 0.10-0.20% and Mn 0.35-0.50%
Also, there are other types of carbon structure steel such as stainless steel, die steel, and tool steel. Stainless steel has higher corrosion resistance and heat resistance than carbon structure steel. Die steel has a higher hardness and abrasion resistance than carbon structure steel. Tool steel is more heat resistant than carbon structure steel.
The grade and chemical composition of carbon structure steel depend on the application and usage. It is important for the customer to choose the right grade and designations for their application in order to get the best performance from the steel.
