ASTM A572

ASTM A572 is a specification for high-strength low alloy (HSLA) steel. It covers a variety of structural shapes and forms, including steel plates. Coils may not be certified to A572 until cut into individual lengths.

As a high-strength low alloy specification, ASTM A572 dictates microalloy requirements through Types. Types 1, 2, 3, and 5 have different chemical limits for each of the three microalloys, with type 5 additionally including a nitrogen requirement.

Available Designations

High-Strength Low Alloy Steel (HSLAS): furnished to a chemical composition and defined mechanical properties. HSLA steels contain strengthening microalloys (niobium, vanadium, titanium) singly or in combination.

A572 HSLAS Steel^A

Listed designations

^A Yield strength, tensile strength, and elongation guaranteed in the transverse direction.

Grade 42

Grade 50

Grade 55

Grade 60

Grade 65

ASTM A572 Characteristics

Property

specification

Ease of Fabrication

The HSLA grades outlined in ASTM A572 serve as a reasonable benchmark for fabrication. Welding, thermal cutting, and basic forming can usually be accomplished without extra precautions.

Weldability

Increased carbon content is associated with increased hardenability, leading to the risk of cracking after welding. In this specification, HSLAS steels are available with carbon maximum ranges from 0.21% for grade 42 to 0.26% for grade 65.

Richer chemistries increase the CEV, so stronger grades require more welding finesse.

Steel Warehouse can limit carbon contents to improve thermal cutting, formability, and welding performance.

Thermal Cutting

Laser and plasma cutting is similar to weldability in terms of the heated cut edge hardening and cracking.

Bendability

ASTM A572 refers to ASTM A6 for bending guarantees.

Defined Sizes

ASTM A572 defines sizes by product category and grade; steel plates have a maximum thickness of 6 inches for grade 42, with the higher strengths having thinner maximum sizes. All plate sizes are defined up to at least 1-1/4 inches.