European S235JR (EN 10025-2) is the direct substitute for GB Q235B channels, with fully aligned properties for light-load applications:
Mechanical Properties:
Yield Strength: S235JR (235 MPa ≤16 mm) vs. Q235B (235 MPa ≤16 mm)-identical, ensuring same light-load capacity (e.g., residential framing).
Tensile Strength: S235JR (360–510 MPa) vs. Q235B (375–500 MPa)-overlapping ranges, no performance gaps.
Elongation: S235JR (26% min) vs. Q235B (26% min)-identical ductility, allowing bending to 90° without cracking.
Chemical Composition:
Carbon: S235JR (max 0.24%) vs. Q235B (max 0.22%)-minor difference, no impact on weldability.
Manganese: S235JR (0.40–1.20%) vs. Q235B (0.30–0.65%)-S235JR's higher range boosts strength slightly but retains workability.
S235JR is used in European light construction (e.g., small warehouses) just as Q235B is in China, making it a seamless substitute with no design changes needed.