GB/T700 Q235B Carbon Structural Steel

GB/T700 Q235B is the most common carbon structural steel. In Q235B grade, Q235 means the minimum yield strength 235 MPa, and B represents 20 temperature impact test. GB/T700 Q235B Steel Plate are used in Construction of Bridges, Highway Construction and Other Engineering construction.
GB/T700 Q235B Steel Chemical Composition:
C < 0.22
Si < 0.35
Mn < 1.4
P < 0.045
S < 0.045
Cr < 0.3
Ni < 0.3
Cu < 0.3
N < 0.008
As < 0.08
Fe Rest
It's allowed to exceed N content up to 0.014% in finished products. On exceeding N for every 0.001% max P content reduces by 0.005%.
by agreement: C > 0.20
GB/T700 Q235B Mechanical Properties:
For section of thickness >100mm is allowed to reduce the lower limit of strength up to 20N/mm2
Thickness: < 16 mm ;
Yield Strength: > 235 MPa
Tensile Strength: 370 - 500 MPa
Elongation: > 26 %
Impact energy KV 20°С: > 27 J
Thickness: 16 - 40 mm ;
Yield Strength: > 225 MPa
Tensile Strength: 370 - 500 MPa
Elongation: > 26 %
Impact energy KV 20°С: > 27 J
Thickness: 40 - 60 mm ;
Yield Strength: > 215 MPa
Tensile Strength: 370 - 500 MPa
Elongation: > 25 %
Impact energy KV 20°С: > 27 J
Thickness: 60 - 100 mm ;
Yield Strength: > 215 MPa
Tensile Strength: 370 - 500 MPa
Elongation: > 24 %
Impact energy KV 20°С: > 27 J
Thickness: 100 - 150 mm ;
Yield Strength: > 195 MPa
Tensile Strength: 370 - 500 MPa
The differences of Q235A and Q235B when using as vessel plate:
Q235A: design pressure 1.0Mpa maximum, 16 mm thick maximum
Q235B: design pressure 1.6Mpa maximum, 20 mm thick maximum
Both shall not be used in toxic substances. Q235A shall not be used in liquefied petroleum gas.