This specification covers an aircraft-quality, low-alloy steel in the form of mechanical tubing.This product has been used typically for parts, with section thickness of 0.50 inch (12.7 mm) and under at time of heat treatment, requiring a through-hardening steel capable of developing hardness as high as 35 HRC when properly hardened and tempered and for parts of greater thickness requiring proportionately lower hardness, but usage is not limited to such applications.
