From the comparion, we find that though ASTM A131 AH36 steel and so called ASTM A131 AH36 steel equivalent materials have much in common. But they are not totally the same. Some even have different impact test requirements. As we know the ASTM A131 AH36 steel is shipbuilding steel, the ship needs to understand waves and corrossion of sea water. It is not safe to use the so called ASTM A131 AH36 steel equivalent to build ships. They can only be used in some not so important parts on the ships.Some regard Q345B, A572 Gr.50, S355JR, ST52-3 etc. high strength low alloy steel as ASTM A131 AH36 steel equivalent. Is that reliable? Let us make a comparion in those steel materials.
Grade | Chemical composition % | |||||||||||||
C (t≤16mm) | Si | Mn | P | S | Nb | V | Ti | Cr | Ni | Cu | N | Mo | Other | |
Q345B | 0.20 max | 0.50 max | 1.70 max | 0.035 max | 0.035 max | 0.07 max | 0.15 max | 0.20 max | 0.30 max | 0.50 max | 0.30 max | 0.012 max | 0.1 max | - |
A572 Gr.50 | 0.23 max | 0.40 max | 1.35 max | 0.04 max | 0.05 max | 0.005 -0.05 |
- | - | - | - | - | - | - | - |
- | 0.01-0.15 | - | - | - | - | - | - | - | ||||||
0.005 -0.05 |
0.01-0.15 | - | - | - | - | - | - | Nb+V 0.02-0.15 | ||||||
- | 0.06 max | 0.006 -0.04 |
- | - | - | 0.003 -0.015 |
- | - | ||||||
S355JR | 0.27 max | 0.6 | 1.70 max | 0.045 max | 0.045 max | - | - | - | - | - | 0.60 max | 0.014 max | - | - |
ST52-3 | 0.22 max | 0.50 max | 0.50 max | - | - | - | - | - | - | - | - | - | ||
A131 AH36 | ≤0.18 | ≤0.50 | 0.90-1.60 | ≤0.030 | ≤0.030 | 0.02 -0.05 |
0.05-0.10 | ≤0.02 | ≤0.20 | ≤0.40 | ≤0.30 | ≤0.08 | Als ≥0.015 |
Grade | Yield strength ReH/(N/mm2) (t≤16mm) min | Tensile strength Rm/(N/mm2) (3mm≤t≤16mm) | Elongation A/%(3mm≤t≤40mm) min | Charpy V test | |
Temperature/℃ | Impact energy (Longitudinal)/J min | ||||
Q345B | 345 | 470-630 | 20 | 20 | 34 |
A572 Gr.50 | 345 | 450 | 18 | - | - |
S355JR | 355 | 470-630 | 22 | 20 | 27 |
ST52-3 | 355 | 490-630 | 22 | 0 | 27 |
A131 AH36 | ≥355 | 490-620 | ≥21 | 0 | 34 |