ASTM A572. The ASTM A572 specification is the Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel for plates used in general construction and structural applications. ASTM A572 includes five grades with specified minimum yield strengths of ASTM A572 Steel Plate - A572 Grade 42, 50, 55, 60, 65 ASTM A572 steel plate is made of ASTM AA572, a High-Strength Low-Alloy, Columbium-Vanadium Structural Steel. There are five grades of high-strength low-alloy structural steel shapes, plates, sheet piling, and bars. Grades 42 , 50 , and 55  are best for riveted, bolted, or welded structures.