GB/T 1591 and EN 10025 are two widely used standards for low-alloy high-strength structural steels. GB/T 1591 defines Chinese grades like Q345 and Q460, while EN 10025 defines European grades such as S355 and S460.
This article compares the scope, grade systems, chemical and mechanical requirements, and application compatibility between GB/T 1591 and EN 10025-2 (S355/S460).
Overview of Each Standard
| Aspect | GB/T 1591-2018 | EN 10025-2 (S355/S460) |
|---|---|---|
| Region | China | European Union |
| Scope | Low-alloy high-strength structural steels | Hot-rolled structural steels (non-alloy & alloy) |
| Delivery Form | Plates, sheets, profiles, seamless tubes | Plates, profiles, hot-rolled H/I beams, tubes |
| Weldability | Generally good, not quantified via Pcm | Pcm and CEQ defined in technical annexes |
| Impact Testing | Optional or grade-dependent | Mandatory for J2/J0/K2 suffix grades |
Grade Comparison Table
| GB/T 1591 Grade | Closest EN 10025 Equivalent | Notes |
|---|---|---|
| Q235B | S235JR | Low strength baseline steel |
| Q345B/C/D/E | S355JR/J0/J2 | Most common equivalence, matched by yield |
| Q390D | Between S355 and S420 grades | No exact EN match; closer to S420 |
| Q460C/D/E | S460J0/J2 | High-strength low-alloy equivalent |
| Q550/Q620/Q690 | No standard EN 10025 equivalent | Comparable to EN 10149 / EN 10210 or S500MC |
📌 Note: European grades include suffixes like JR, J0, J2, which indicate impact toughness at 20°C, 0°C, and -20°C respectively.
Mechanical Properties Comparison
| Property | Q345D (GB/T 1591) | S355J2 (EN 10025-2) |
|---|---|---|
| Yield Strength (MPa) | ≥345 MPa (thickness ≤16 mm) | ≥355 MPa |
| Tensile Strength | 470–630 MPa | 470–630 MPa |
| Elongation | ≥21% | ≥22% |
| Impact Test | 27J @ -20°C (for D grade) | 27J @ -20°C (J2 grade) |
| Property | Q460D | S460J2 |
|---|---|---|
| Yield Strength | ≥460 MPa | ≥460 MPa |
| Tensile Strength | 550–720 MPa | 540–720 MPa |
| Elongation | ≥17% | ≥17% |
| Impact Test | 27J @ -20°C (for D grade) | 27J @ -20°C |
📌 The mechanical behavior is closely aligned across both standards when equivalent suffixes (like D ↔ J2) are used.
Chemical Composition Comparison (Example: Q345D vs S355J2)
| Element | Q345D (max %) | S355J2 (max %) |
|---|---|---|
| C | 0.18 | 0.20 |
| Mn | ≤1.70 | ≤1.60 |
| Si | ≤0.50 | ≤0.50 |
| S | ≤0.030 | ≤0.025 |
| P | ≤0.030 | ≤0.025 |
| CEQ / Pcm | Not specified | Required in annex |
📌 S355J2 includes stricter phosphorus/sulfur limits and requires CEQ (Carbon Equivalent) calculation for weldability.
Applications
Both standards are used in:
- Steel structures: bridges, towers, warehouses
- Heavy machinery: cranes, excavators, piling rigs
- Railway & infrastructure: tunnels, stations, platforms
- Renewable energy: wind turbine frames, solar brackets
📌 EN 10025 is mandatory in CE/EU-regulated projects, while GB/T 1591 is widely used in Asian OEM and EPC projects.
Can GB/T 1591 Replace EN 10025?
| Situation | Feasibility |
|---|---|
| Export to EU construction project | ⚠️ Conditional — CE certification required |
| General mechanical structure | ✅ Yes |
| CE-marked projects / Eurocode design | ✅ Possible via certified EN-grade equivalent |
| Asian-made equipment for global use | ✅ Acceptable with traceability and certification |
At YIGE Steel, although we mainly produce to Chinese GB/T 1591 standards, we are CE-certified and have extensive experience in supplying material equivalent to EN 10025, including:
- CE-compliant S355J2H / S460J2H grade tubes
- Customized Q345/Q460 products that meet EN impact and mechanical requirements
- Third-party inspection (e.g., SGS, BV) upon request
- Material traceability reports, weldability data, and CE-marked documentation
✅ So yes — for many projects, we can provide GB or EN labeled material that meets CE requirements.
Conclusion
GB/T 1591 and EN 10025 both offer strong, weldable low-alloy structural steels. While they differ in documentation and compliance, their mechanical and chemical properties are often closely aligned.
At YIGE Steel, we help bridge this gap by offering:
- GB/T 1591 grades (Q345D/E, Q460D/E, Q690) with full traceability
- CE-certified production lines for S355J2H / S460J2H-equivalent materials
- Heat treatment, impact test, weldability evaluation (Pcm/CEQ), and export-ready inspection reports
- Engineering support for cross-standard substitution and structural material conversion
Let us help you meet both performance and compliance goals: stella.yu@yige-steel.com
