SAE AMS6299F

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.These products have been used typically for parts to be carburized requiring high minimum core hardness with wide range in sections 0.375 inch (9.5 mm) and under in thickness, but usage is not limited to such applications. The core may or may not be machinable after hardening.