Alloy steel is steel that is alloyed with a variety of elements in total amounts between 1.0% and 50% by weight to improve its mechanical properties. Strictly speaking, every steel is an alloy, but not all steels are called "alloy steels". The simplest steels are iron (Fe) alloyed withcarbon (C) (about 0.1% to 1%, depending on type). However, the term "alloy steel" is the standard term referring to steels with otheralloying elements added deliberately in addition to the carbon. Common alloyants include manganese (the most common one),nickel, chromium, molybdenum, vanadium, silicon, and boron. Less common alloyants include aluminum, cobalt, copper, cerium,niobium, titanium, tungsten, tin, zinc, lead, and zirconium.
ASTM A 335, GR P1, P2, P5, P9, P11, P22, P91
ASTM A 387, Class: I/II, Grade: 11, 22, 5, 9, 12, 1
A182, Gr. F1, F2, F11, F22, F5, F9, F91
ASTM A 234, Gr. WP1, WP11, WP22, WP5, WP9, WP91, (IBR/Non IBR)
ASTM A 182, Grade F1, F11, F22, F5, F9, F91 (IBR & NON IBR)
ASTM A 182, GR F1, F11, F22, F5, F9, F91