Form

This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.

Application

These products have been used primarily for parts 3.5 inches (90 mm) and under in nominal section-thickness at time of heat treatment requiring a through-hardening steel capable of developing hardness as high as 40 HRC and also for parts with thicker cross-section which require proportionately lower hardness, but usage is not limited to such applications.