ASTM A572 grade 50 plate

Dec 24, 2025

ASTM A572 Grade 50 is classified as a High-Strength Low-Alloy (HSLA) steel under the ASTM standard. It is also commonly referred to as a high-tensile, low-alloy Ni-V steel, due to the controlled addition of alloying elements that enhance its mechanical performance.

The ASTM A572 specification covers four strength grades, among which Grade 50 is the most widely used. This low-alloy steel grade is extensively applied in structural engineering, heavy construction equipment, building frameworks, heavy anchoring systems, truck frames, and other applications where a high strength-to-weight ratio is critical.

ASTM A572 Grade 50 is typically manufactured in the form of steel plates, structural channels, and heavy steel beams, making it suitable for load-bearing and large-span structures.

Thanks to its combination of high yield strength, good weldability, and improved toughness, ASTM A572 Grade 50 helps engineers reduce overall material weight while maintaining structural safety and durability, which is especially important in modern infrastructure and transportation projects.

Chemical Composition of ASTM A572 Gr 50 Plate

Grade	C (t≤16mm)	Si	Mn	P	S	Cu	N	Mo
A572 Gr 50	0.23 max	0.40 max	1.35 max	0.04 max	0.05 max	-	-	-
S355JR	0.27 max	0.60 max	1.70 max	0.045 max	0.045 max	0.60 max	0.014 max	-
ST52-3	0.22 max	-	-	0.50 max	0.50 max	-	-	-
SM490B	0.20 max	0.55 max	1.60 max	0.035 max	0.035 max	-	-	-
Q345B	0.20 max	0.50 max	1.70 max	0.035 max	0.035 max	0.30 max	0.012 max	0.1 max

Mechanical Properties of ASTM A572 Grade 50 Plate

Grade	Yield strength ReH/(N/mm2) (t≤16mm) min	Tensile strength Rm/(N/mm2) (3mm≤t≤16mm)	Elongation A/%(3mm≤t≤40mm) min	Charpy V test
Grade	Yield strength ReH/(N/mm2) (t≤16mm) min	Tensile strength Rm/(N/mm2) (3mm≤t≤16mm)	Elongation A/%(3mm≤t≤40mm) min	Temperature/℃	Impact energy (Longitudinal)/J min
A572 Gr 50	345	450	18	-	-
S355JR	355	470-630	22	20	27
ST52-3	355	490-630	22	0	27
SM490B	295	490-610	18
Q345B	345	470-630	20	20	34