What is SS400 Steels? SS400 steel is a structural hot Rolled steel in the form of plates, sheets & strips for general structural applications. SS400 is a material grade and designation defined in JIS G 3101 standard. JIS G 3101 is a Japanese material standard for hot Rolled steel plates, sheets, strips for general structural usage. The structural quality hot rolled SS400 steel is more reliable in its tensile strength than SS330 steel.
Dimensional Characteristics of SS400 Steels: The applicable thickness for this SS400 material as defined in the JIS 3101 starts from 6 mm to 120 mm.
The Chemical Composition of SS400 Steels: JIS G 3101 defines the chemical composition of SS400 steels as under:
Carbon (C) is not identified in the standard.
Manganese (Mn) is not identified in the standard.
Maximum percentage of Phosphorous (P) is 0.050 percent.
Maximum percentage of Sulphur (S) is 0.050 percent.
Remaining is iron (Fe) percentage and with few negligible impurities.
Mechanical Properties of SS400 Steels: The tensile strength of the SS400 Steels is expressed in Newton per millimeters and it must be at-least 400 N/mm2 (MPa) and maximum can be 510 N/mm2 (MPa). The yield strength is minimum 205 to minimum 245 N/mm2 (MPa) depending on the thickness. The yield strength for thickness below 16 mm is minimum 245 N/mm2 (MPa) whereas for higher gauges above 100 mm is minimum 205 N/mm2 (MPa). The elongation property of SS400 steel varies with the ranges of thickness. The minimum percentage ranges for elongation is 17% thicknesses till 16 mm, 21% for thicknesses till 40 mm, and 23% greater than 50 mm.
SPHC steel comparison with this grade of SS400 material will show how general structure hot rolled steel differs with commercial quality SPHC steel in chemical composition & mechanical properties.
Applications of this kind of steel are in making structural tubes, pipes, rods, and various structural sectional steels.