SM520 Structural Steel Plate

SM520 high-strength structural steel plate for welded structures, offering superior toughness, weldability, and load capacity for heavy engineering projects.

High Strength Grade: Minimum yield strength of 355 MPa for heavy-duty welded structures.
Excellent Weldability: Low carbon equivalent ensures stable welding performance.
Improved Toughness: Guaranteed Charpy V-notch impact values at low temperatures.
Wide Thickness Range: Suitable for thick plate fabrication and heavy equipment.
Reliable Durability: Consistent mechanical properties across batches and sections.

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SM520 Steel Description

SM520 is a high-tensile structural steel specified in JIS G3106, used for welded structures such as bridges, ships, offshore platforms, storage tanks, and heavy machinery.
It is an upgraded version of SM490, with higher yield strength (≥355 MPa) and enhanced toughness for demanding structural applications.

SM520 is available in grades SM520B and SM520C, both with superior impact resistance:

SM520B: Impact test guaranteed at 0°C
SM520C: Impact test guaranteed at -20°C

The steel combines excellent weldability, formability, and fatigue resistance, making it ideal for large welded components in civil and industrial construction.

SM520 Technical Data Sheet

SM520 Chemical Composition
Element	Max / Range (%)
Carbon (C)	≤ 0.20
Silicon (Si)	≤ 0.55
Manganese (Mn)	≤ 1.70
Phosphorus (P)	≤ 0.035
Sulfur (S)	≤ 0.035

SM520 Mechanical Properties
Property	Typical Value
Yield Strength (ReL)	≥ 355 MPa
Tensile Strength (Rm)	520–640 MPa
Elongation (A5)	≥ 20%
Impact Energy (Charpy V)	SM520B: 27 J @ 0°C / SM520C: 27 J @ -20°C