SAE AMS4127L PDF
This specification covers an aluminum alloy in the form of die forgings not over 4 inches (102 mm) in nominal thickness at time of heat treatment , hand forgings with as-forged thickness not exceeding 8 inches (203 mm) and the cross-sectional area not greater than 256 square inches (1652 cm2), forged or rolled rings 3.5 inches (89 mm) and under in nominal thickness at time of heat treatment and having an OD-to-wall thickness ratio of 10:1 or greater, and stock of any size for forgings and rings (see 8.6).