Regional QC practices differ:
China (GB/T 2970):
Ultrasonic testing (UT) for No. 40+ I-beams, with 100% visual inspection for surface cracks (allowable defect size: <0.5mm).
United States (ASTM A6/A709):
Magnetic particle inspection (MPI) for bridge I-beams (W14×90), with yield strength testing at 345–365 MPa.
Europe (EN 10163-2):
Hot-rolled I-beams (IPB) must pass bend tests (180° without cracking), with chemical analysis limiting sulfur ≤0.035%, phosphorus ≤0.035%.
Key trends: I-beams are evolving toward higher-strength grades (e.g., Q460 in China) and sustainable production (e.g., hydrogen-reduced steel in Europe), balancing cost and performance in emerging infrastructure demands.