ASTM A 646/A 646M

This specification deals with the standard requirements for premium quality alloy steel semifinished rolled or forged blooms and billets for reforging into aircraft and aerospace critical parts such as landing-gear forgings. Covered here are three basic classifications of steel, namely: Class I, steel manufactured by vacuum-induction melting or consumable-electrode vacuum melting process; Class II, air-melted steel manufactured by electric-furnace vacuum degassing process; Class III, air-melted steel manufactured by electric-furnace ladle refining and vacuum degassing processes. Steel materials shall be heat-treated and hot-worked by either hot rolling or forging. Alloy steels shall be examined by heat and product analyses and hardenability tests, and shall conform to chemical composition and maximum annealed Brinell hardness requirements. Quality evaluation tests, such as macrotech, microcleanliness, and nondestructive ultrasonic (both immersion and contact examination) inspection, shall be performed as well.