Q345B low carbon alloy steel

Q345B is a grade B low carbon alloy steel. Its main features are good comprehensive performance, good low temperature performance, cold stamping performance, good welding performance and machinability.

Q represents the yield of this material, and 345 in the back refers to the yield value of this material, which is around 345MPa. And will decrease the yield value as the thickness of the material increases.

Q345B is similar to the naming method of Q235:
Q345A, Q345B, Q345C, Q345D, Q345E. This is the distinction of grades, which means that the temperature of the impact is different.

Q345B is widely used in bridges, vehicles, ships, buildings, pressure vessels, etc.

Q345B low carbon alloy steel chemical composition:

Grade

C

Si

Mn

P

S

V

Nb

Al

Ti

Cr

Ni

Cu

Q345A

≤0.20

≤0.50

≤1.70

≤0.035

≤0.035

≤0.15

≤0.07

-

≤0.20

≤0.30

≤0.50

≤0.30

Q345B

≤0.20

≤0.50

≤1.70

≤0.035

0.035

≤0.15

≤0.07

-

≤0.20

≤0.30

≤0.50

≤0.30

Q345C

≤0.20

≤0.50

≤1.70

≤0.030

≤0.030

≤0.15

≤0.07

≥0.015

≤0.20

≤0.30

≤0.50

≤0.30

Q345D

0.18

≤0.50

≤1.70

≤0.030

≤0.025

≤0.15

≤0.07

≥0.015

≤0.20

≤0.30

≤0.50

≤0.30

Q345E

≤0.18

≤0.50

≤1.70

≤0.025

≤0.020

≤0.15

≤0.07

≥0.015

≤0.20

≤0.30

≤0.50

≤0.30

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