The differences between Q345 steel plate and Q355 steel plate
Q345 steel plate is a low-alloy steel plate with five grades of A, B, C, D, and E. Q345A does not do low temperature impact test, and q345b, Q345C, Q345D, Q345E all do impact test, and the temperature is 20˚C, 0˚C , -20˚C, -40˚C. The implementation standard of Q345 steel plate: GB/T1591-2008 Low Alloy High Strength Steel.
Q345 steel plate Chemical Composition
| Chemical Composition Content (≤%) |
| Steel Grade |
Quality Grade |
C |
Si |
Mn |
P |
S |
Cr |
Ni |
Mo |
Cu |
Ti |
N |
Nb |
V |
B |
Als, ≥ |
| Q345 |
Q345A |
0.20 |
0.50 |
1.70 |
0.035 |
0.035 |
0.30 |
0.50 |
0.10 |
0.30 |
0.20 |
0.012 |
0.07 |
0.15 |
– |
– |
| Q345B |
0.035 |
0.035 |
| Q345C |
0.030 |
0.030 |
0.015 |
Q355 steel plate is a low-alloy steel plate, which can be divided into five grades: B, C, D, E, and F. Q355B, Q355C, Q355D, Q355E, Q355F are all subjected to impact test, and the temperature is 0˚C, -20˚C, -40˚ C. -60℃. Q355 steel plate implementation standard: GB/T1591-2018 Low Alloy High Strength Steel.
Q355 steel plate Chemical Composition
| Steel Grade |
Quality Grade |
C % (≤) |
Si % (≤) |
Mn (≤) |
P (≤) |
S (≤) |
Cr (≤) |
Ni (≤) |
Cu (≤) |
N (≤) |
| Q355 |
Q355B |
0.24 |
0.55 |
1.6 |
0.035 |
0.035 |
0.30 |
0.30 |
0.40 |
0.012 |
| Q355C |
0.20 |
0.030 |
0.030 |
0.012 |
| Q355D |
0.20 |
0.025 |
0.025 |
– |
