Hot Rolled Mild Steel JIS G3131 SPHD

What is JIS G3131 SPHD Steels?

JIS G3131 SPHD refers to high strength hot rolled mild steel grades per Japanese Industrial Standard G3131. SPHD stands for “Steel Plate for High Strength Bridge and Common Structures”. These perform better than SPHC grades in critical applications.

Why Purchasing sample of this type of steel is significant for making your product?

Obtaining samples of JIS G3131 SPHD steel lets manufacturers verify the material meets design needs before a large order. Properties like composition, mechanical strengths are quality checked on samples rather than full batches. This reduces risks while trials and testing can also be conducted.

What is Hot Rolled Mild Steel?

Hot rolled mild steel goes through controlled rolling at high temperatures above the steel’s recrystallization point. This enhances its mechanical properties compared to cold rolled or forged materials of the same composition.

Why is JIS G3131 SPHD material called hot rolled Steel?

JIS G3131 SPHD grades undergo hot rolling during manufacture. Heating above the recrystallizing temperature allows precise shape setting through calibrated rolling before air cooling to room temperature in the final profile.

Hot Rolled Mild Steel JIS G3131 SPHD
Hot Rolled Mild Steel JIS G3131 SPHD

Available Forms in Shangang Steel

Common forms include channels, beams, angles and wide flats in various cross-sections as per construction needs. Standard sizes range from 5mm to 250mm thickness and up to 3000mm width. Custom shapes are also manufactured sometimes.

Characteristics of JIS G3131 SPHD Steels

These are medium carbon steels offering higher tensile strengths ranging from 440-590MPa compared to regular SPHC grades. Surfaces range from mill scale to ground levels based on specified finishes.

The Chemical Composition of JIS G3131 SPHD Steels

Composition as per JIS G3131 includes 0.15-0.25% carbon and 0.6-1.0% manganese with small additions to optimize mechanical properties for structural use.

Mechanical Properties of JIS G3131 SPHD Steels

Yield Strength ranges from 370-480MPa. Tensile Strength ranges from 440-590MPa. Elongation exceeds 16% indicating good ductility even at higher strengths. Impact properties and fatigue resistance are high.

Equivalent Material Grades in Other International Standards

Comparable grades as per other standards are ASTM A572 GR 50, EN S355JR/JO in European specifications having similar mechanical and chemical attributes.


Suitable for bridges, offshore structures, pressure vessels, cargo containers and other applications requiring elevated strength mild steel qualities. Widely used in construction sector for critical load bearing members.