This specification covers an aluminum alloy in the form of extruded bars, rods, and profiles (shapes).These extrusions have been used typically for machined parts requiring dimensional stability during machining processes and for parts requiring high strength and damage tolerance, where fabrication does not normally involve welding, but usage is not limited to such applications.Certain processing procedures may cause this product to become susceptible to stress-corrosion cracking; ARP823 recommends practices to minimize such conditions.