ASTM A 533 Grade B is a manganese-molybdenum-nickel alloy steel for use in the quenched-and-tempered condition for plate for the construction of pressure vessels and other pressure equipment. It is used in 6 to 12-inch sections and is the most widely used steel for nuclear reactor pressure vessels. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-328. Producer or source: Alloy steel mills and foundries.