ASTM A572 Grade 50 High-Strength Low-Alloy Steel

ASTM A572/A572M · Updated: 2026-05-23

ASTM A572 Grade 50 is a high-strength low-alloy (HSLA) structural steel with columbium-vanadium micro-alloying that delivers 345 MPa minimum yield strength—38% stronger than A36. Its superior strength-to-weight ratio allows engineers to reduce structural weight by 20-30% compared to A36 designs. Commonly used for bridges, transmission towers, construction equipment, and heavy-duty structural applications. Available in plates, shapes, and sheet piling with good weldability using low-hydrogen practices.

Quick Facts

CategoryCarbon Steel
StandardASTM A572/A572M
Density7.85 g/cm³
Yield Strength345 MPa (50 ksi)
Tensile Strength450 MPa (65 ksi)

Global Equivalents & Cross-Reference

Alternative Standard / GradeAction
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Calculate the weight based on this material's density: 7.85 g/cm³

Frequently Asked Questions

Can A572 Grade 50 replace A36 in structural design?

Yes, A572 Gr 50 can replace A36 in most structural applications with significant weight savings. The higher strength allows lighter sections, but designers must check deflection and stability limits which may govern with thinner sections. Welding procedures should use matching-strength filler metals (e.g., E70XX electrodes).