ASTM A204/A204M specification covers molybdenum alloy steel plates, intended particularly for welded boilers and other pressure vessels. Plates under ASTM A204/A204M specification are available in three grades having different strength levels: Grade A; Grade B; and Grade C. The steel shall be killed. The steel shall conform to the chemical requirements specified. Tension tests on plates shall conform to the requirements specified.ASTM A204/A204M standard main steel grade:ASTM A204 Grade A,B,C(A204GRA,B,C)