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Steel grades are used to distinguish different types of steel based on their unique characteristics. Steel grades are also frequently used to assign different grades of steels.
China
In China, the most commonly used steel grades are Q195-Q345.
Q195 is a type of carbon structural steel, it generally contains more than 0.12% carbon and less than 0.65% manganese. It is widely used in bridges, buildings and other structures.
Q235 is a type of carbon structural steel, it has a medium carbon content, generally between 0.14-0.22%. It is used for constructional purposes and has good plasticity, toughness and welding properties.
Q345 is a low-alloy steel with a carbon content of 0.2-0.9%. It is widely used for bridges, vessels and other structures.
USA
The most commonly used steel grades in the United States are A36, A572 and A588.
A36 is a type of carbon structural steel, it has a relatively low tensile strength and is commonly used for general structures.
A572 is a high-strength, low-alloy steel grade, it has a higher strength than A36 and is commonly used for general structural applications.
A588 is a low-alloy steel grade with an elevated level of corrosion resistance, it is commonly used for bridge and other structures that are located in humid and salty environments.
UK
The most commonly used steel grades in the UK are S235, S275 and S355.
S235 is a low carbon steel grade, it is typically used for structural applications and it has good cold forming properties.
S275 is a carbon structural steel with a medium carbon content, it has a good combination of strength and ductility.
S355 is a low-alloy high-strength stainless steel, it is commonly used for bridges, ships and other structures.
Japan
The most commonly used steel grades in Japan are SS400, SS490 and SM41A.
SS400 is a low-carbon steel grade with a tensile strength and yield strength of 400 MPa. It is commonly used for general structural purposes.
SS490 is a medium-carbon steel grade with a tensile strength and yield strength of 490 MPa. It is used for special structural applications.
SM41A is a Japanese equivalent of SAE 1045 steel, it is a medium-carbon steel grade with a tensile strength and yield strength of 41 MPa. It is commonly used for machinery parts.
