European S235JR (EN 10025-2) is the direct substitute for China's GB Q235B H-beam, with fully aligned properties for light structural applications:
Mechanical Properties:
Yield Strength: S235JR (235 MPa min for ≤16 mm) vs. Q235B (235 MPa min for ≤16 mm)-identical, ensuring both grades support the same light loads (e.g., residential framing, small machinery).
Tensile Strength: S235JR (360–510 MPa) vs. Q235B (375–500 MPa)-overlapping ranges, with no practical difference in maximum load capacity.
Elongation: S235JR (26% min over 50 mm) vs. Q235B (26% min over 50 mm)-identical ductility, ensuring both grades can be fabricated via bending and welding.
Impact Toughness: S235JR (27 J min at +20°C) vs. Q235B (27 J min at 20°C)-matching toughness for ambient-temperature use.
Chemical Composition:
Carbon: S235JR (max 0.24%) vs. Q235B (max 0.22%)-minor difference, with both levels low enough to ensure weldability.
Manganese: S235JR (0.40–1.20%) vs. Q235B (0.30–0.65%)-S235JR's higher range boosts strength slightly but does not affect workability.
Phosphorus/Sulfur: Both capped at 0.045% (S235JR) and 0.045% (Q235B)-identical impurity limits to prevent brittleness.
S235JR is widely used in European light construction, just as Q235B is in China, making it a seamless substitute for projects requiring GB-equivalent performance at lower strength levels.