ASTM A572 covers low-alloy, high-strength steels of four different yield strength levels, 42, 50, 60 and 65 ksi. Strengthening is provided by small additions of columbium, vanadium, columbium+vanadium or vanadium+nitrogen. Maximum carbon is at 0.21 to 0.26%, depending on thickness, as shown in the tabulation under composition. This datasheet provides information on composition and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-448. Producer or source: Alloy steel mills and foundries.