Q235B steel plate is a kind of low carbon steel. The national standard GB/T 700-2006 "Carbon Structural Steel" has a clear definition. Q235B is one of the most common steel products in China. It is cheap and can be used for most products that do not require high performance.
Consists of Q+number+quality grade symbol+deoxidation method symbol. Its steel number is prefixed with "Q", which represents the yield point of the steel, and the following number represents the yield point value in MPa. For example, Q235 represents a carbon structural steel with a yield point of 235 MPa.
If necessary, a symbol indicating quality grade and deoxidation method can be marked after the steel number. The quality grade symbols are A, B, C, D. Symbol of deoxidation method: F means boiling steel; b means semi-killed steel; Z means killed steel; TZ means special killed steel. Killed steel may not be marked with symbols, that is, both Z and TZ may not be marked. For example, Q235-AF represents Class A boiling steel.
Carbon steel for special purposes, such as bridge steel, ship steel, etc., basically uses the expression method of carbon structural steel, but the letter indicating the purpose is added at the end of the steel number.
Carbon C: <=0.20
Silicon Si: <=0.35
Manganese Mn: <=1.4
Sulfur S: <=0.045
Phosphorus P: <=0.045
Chromium Cr: allowable residual content <=0.30
Nickel Ni: allowable residual content <=0.30
Copper Cu: allowable residual content <=0.30
Yield strength: <=16mm: >=235
16-40: >=225
40-100: >=215
100-150: >=195
150-200: >=185.
Tensile strength: 370-500.
Impact test: Temperature: 20℃: >=27
Q235B has a certain℃of elongation, strength, good toughness and castability, and is easy to stamp and weld. It is widely used in the manufacture of general mechanical parts. Mainly used for welding structural parts with high quality requirements in construction and bridge engineering.
