1.1 This practice is intended, when specified by material specification or purchase order, for the use in the heat treatment of aluminum alloy castings from all casting processes.1.1.1 The heat treatment of aluminum alloy castings used in specific aerospace applications is covered in AMS 2771 and specific AMS material specifications.1.1.2 The heat treatment of wrought aluminum alloys is covered in Practice B 918.1.2 The values stated in either inch-pound units or SI units