Products Overview
| Steel Grade | Type | Manufacturing | Strength & Alloying | Applications |
|---|---|---|---|---|
| Q235 | Mild Carbon Steel | Hot-rolled or cold-rolled; various forms: plates, sheets, rods, rebars, sections | Moderate strength (~235 MPa yield); low alloy content; excellent plasticity, toughness, weldability | General welded structures, factory buildings, steel bars, bridges, high-voltage towers, vehicles, boilers, containers, scaffolding, mechanical parts with low stress |
| Q345 | Low-Alloy Structural Steel (16Mn class) | Hot-rolled (plate, coil, sheet); normal or hot-rolled state | Higher strength (~345 MPa yield); alloyed with Mn, small amounts of other elements; good low-temperature performance, plasticity, and weldability | Low-pressure vessels, fuel tanks, vehicles, cranes, mining machinery, power stations, mechanical parts, building structures, general metal parts; suitable for temperatures down to −40 °C |
Key Differences
| Feature | Q235 | Q345 |
|---|---|---|
| Yield Strength | 235 MPa | 345 MPa |
| Tensile Strength | 370–500 MPa | 470–630 MPa |
| Plasticity & Toughness | Good | Better, especially at low temperatures |
| Weldability | Excellent | Good, suitable for structural and pressure applications |
| Alloy Content | Low carbon, trace Mn, Si, P, S | Higher Mn (≈1.0–1.6%), small Cr, Ni, Cu in some variants; low alloy steel |
| Temperature Resistance | Normal ambient temperature | Can work at −40 °C and above |
| Applications | Light to moderate structural components | Medium to heavy-duty structures, mechanical parts, pressure vessels, cranes |
Usage Guidance
Q235: Best suited for general construction and non-critical load-bearing parts where ease of fabrication, weldability, and cost are prioritized. Ideal for welded frames, rebar, light machinery, and buildings.
Q345: Chosen for higher-strength or cold environment applications, where enhanced yield and tensile strength, combined with good toughness and weldability, are required. Suitable for cranes, fuel tanks, mining machinery, bridges, and low-temperature structures.
