High strength alloys with excellent machinability widely used in aircraft. Have limited formability and only fair corrosion resistant in the heat treated condition. Not recommended for fusion welding. Used for high strength parts in aircraft and machinery, including gears and bolts and for security vans where strength ids critical. It has a tendency to allow the removal of a greater volume of metal in a single operation for an equipment standard of finish than 6082. Durability, however, is lower and needs a protection coating. Machines better in solution treated condition than fully heat treated. Used for machined parts where these characteristics are critical.