Answer:
EN 10025-2 S355JR H-beam, marketed as "EN 10025-2 S355JR H-Beam for European Construction" on Made-in-China.com, and GB/T 11263 Q355B have similar core strengths but differ in mechanical testing protocols-critical for quality validation.
Tensile testing:
S355JR (EN 10002-1): Uses 25mm gauge length specimens (for 10–16mm thickness). Minimum yield strength 355 MPa, tensile strength 470–630 MPa, and elongation ≥22% (for thickness ≤16mm). Testing speed is 1–10 mm/min until yield, then 20–50 mm/min.
Q355B (GB/T 228.1): Uses 50mm gauge length specimens. Yield strength ≥355 MPa, tensile strength 470–630 MPa, and elongation ≥22%. Speed is 0.00025–0.0025 s⁻¹ (strain rate) for yield, ensuring consistent results across labs.
Impact testing:
S355JR (EN 10045-1): Requires 10×10×55mm V-notch specimens at 20°C, minimum impact energy 27 J. For cold regions, S355J2 (sub-grade) tests at -40°C (27 J).
Q355B (GB/T 229): Mandatory -20°C impact testing (10×10×55mm V-notch), minimum 34 J-stricter than S355JR's 20°C requirement. This reflects China's focus on cold-region performance (e.g., northern provinces).
Bending testing:
S355JR (EN 10045-2): 180° bend test with mandrel diameter 3×thickness (for ≤16mm), no cracks allowed.
Q355B (GB/T 232): 180° bend test with mandrel diameter 2×thickness (stricter), ensuring better ductility.
NDT: Both require ultrasonic testing (S355JR per EN 10160, Q355B per GB/T 2970), but S355JR allows spot testing (20% of beams) for non-critical applications, while Q355B mandates 100% testing for beams ≥16mm. These differences mean S355JR is better suited for mild European climates, while Q355B excels in China's diverse temperature ranges.