Technical specifications and application of weathering steel according to JIS G3114
The JIS G3114 standard regulates the technical delivery conditions for hot-rolled steel products with enhanced atmospheric corrosion resistance. These steel grades are characterized by excellent weldability and are designed for critical load-bearing structures, including bridges, high-rise construction, and infrastructure facilities operating in outdoor environments.
The term “weathering” refers to the material’s ability to form a dense oxide layer (patina) on its surface, which prevents further corrosion from penetrating the metal structure, thereby significantly extending the service life of structures without the need for additional painting.
Engineers at EV Group China highlight the chemical composition of the steel grades provided in the table below, which ensures an optimal balance of strength properties and corrosion resistance.
| Steel | C | Si | Mn | P | S | Cu | Cr | Ni |
|---|---|---|---|---|---|---|---|---|
| SMA400AW, SMA400BW, SMA400CW | <0.18 | 0.15-0.65 | <1.25 | <0.035 | <0.035 | 0.30-0.50 | 0.45-0.75 | 0.05-0.30 |
| SMA400AP, SMA400BP, SMA400CP | <0.18 | <0.55 | <1.25 | <0.035 | <0.035 | 0.20-0.35 | 0.30-0.55 | – |
| SMA490AW, SMA490BW, SMA490CW | <0.18 | 0.15-0.65 | <1.40 | <0.035 | <0.035 | 0.30-0.50 | 0.45-0.75 | 0.05-0.30 |
| SMA490AP, SMA490BP, SMA490CP | <0.18 | <0.55 | <1.40 | <0.035 | <0.035 | 0.20-0.35 | 0.30-0.55 | – |
| SMA570W | <0.18 | 0.15-0.65 | <1.40 | <0.035 | <0.035 | 0.30-0.50 | 0.45-0.75 | 0.05-0.30 |
| SMA570P | <0.18 | <0.55 | <1.40 | <0.035 | <0.035 | 0.20-0.35 | 0.30-0.55 | – |