JIS G3106 Hot Rolled for Welded Structure SM490B Steel

SM490B Steel is a material designation defined in JIS G3106 standard, SM490B Steel is a Hot Rolled Steel for Welded Structure.

What is SM490B Steel?           

SM490B Steel is hot rolled steel for welded structure in the form of plates, sheets & strips for architecture, engineering structures. SM490B steel is a material grade and designation defined in JIS G3106 standard. JIS G3106 is a Japanese material standard for hot rolled steel for welded structure steel plates, sheets, strips for Architecture, Engineering Structures.

The hot rolled steel for welded structure SM490B steel is more reliable in its tensile strength than SM400B steel.

Dimensional Characteristics of SM490B steel:

The applicable thickness for this SM490B steel material as defined in the JIS G3106, it is from 6 mm to 300 mm.

The Chemical Composition of SM490B Steels:

JIS G3106 defines the percentage of chemical composition of SM490B steels as under:

Maximum Carbon (C) percentage is 0.18.

Maximum Manganese (Mn) percentage is 1.65.

Maximum percentage of Phosphorous (P) is 0.035.

Maximum percentage of Sulphur (S) is 0.035.

Maximum percentage of Silicon (Si) is 0.55.

Remaining is iron (Fe) percentage and with few negligible impurities.


Mechanical Properties of SM490B Steels:

The tensile strength of the SM490B Steels is expressed in Newton per millimeters and it must be at-least 490 N/mm2 (MPa) and maximum can be 610 N/mm2 (MPa). The yield strength is minimum 325. The elongation property of SM490B Steel varies with the ranges of thickness.  The minimum percentage range for elongation is 17.


SM400B comparison with this grade of SM490B Steel material will show how SM490B differs with SM400B in chemical composition & mechanical properties.

Applications of this kind of steel are in manufacturing of structures for mining, and drilling rigs. 

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