Low alloy steel ASTM A572 Gr 50 is considered the "working horse" class and is widely used in structural applications, heavy construction equipment, building structures, heavy anchoring systems, truck frames, and applications requiring high strength-to-weight ratios. Low alloy steel ASTM A572 Gr 50 is usually produced into steel H-Beams, Channel steel, and heavy structural beams.
Low alloy steel ASTM A572 Gr 50 equivalent materials such as EN S355J2, DIN ST52-3, JIS SM490B, and GB Q345B have much in common with ASTM A572 Gr 50 H-Beams.
Chemical composition of Low alloy steel ASTM A572 Gr 50 equivalent materials (H-Beams):
| Grade | C (t≤16mm) | Si | Mn | P | S | Cu | N | Mo |
|---|---|---|---|---|---|---|---|---|
| A572 Gr 50 | 0.23 max | 0.40 max | 1.35 max | 0.04 max | 0.05 max | - | - | - |
| S355JR | 0.27 max | 0.60 max | 1.70 max | 0.045 max | 0.045 max | 0.60 | 0.014 | - |
| ST52-3 | 0.22 max | - | - | 0.50 max | 0.50 max | - | - | - |
| SM490B | 0.20 max | 0.55 max | 1.60 max | 0.035 max | 0.035 max | - | - | - |
| Q345B | 0.20 max | 0.50 max | 1.70 max | 0.035 max | 0.035 max | 0.30 | 0.012 | 0.1 |
Mechanical properties of Low alloy steel ASTM A572 Gr 50 equivalent H-Beams:
| 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 Temp/°C | Impact energy J min |
|---|---|---|---|---|---|
| A572 Gr 50 | 345 | 450 | 18 | - | - |
| S355JR | 355 | 470-630 | 22 | 20 | 27 |
| ST52-3 | 355 | 490-630 | 22 | 0 | 27 |
| SM490B | 295 | 490-610 | 18 | - | - |
| Q345B | 345 | 470-630 | 20 | 20 | 34 |
Among low alloy steel ASTM A572 Gr 50 equivalent H-Beams, EN S355JR is most widely used in structural engineering and construction industries. JIS SM490B is also popular mainly in Asia.
With the expansion of China's international business, GB Q345B has become well-known globally on construction sites. Originated in Germany, DIN ST52-3 H-Beams are known to engineers but are less commonly produced today.
In China, Gnee Steel is one of the mills that can supply the full range of ASTM A572 Gr 50 equivalent H-Beams.