This series of aluminum is the original heat treatable alloy group developed in the 1920's.
The
best known, most widely used heat treatable alloy for aircraft and aerospace is 2024. Can be spot and
friction welded but not fusion welded (a few exceptions being tank structures in the Titan Missile). Has good
formability in the annealed temper condition and some formability in the solution treated and aged condition,
but needs intelligent application in complex designs. Has excellent fatigue properties when compared to
other aluminum alloys, excellent strength to weight ratio. Good machinability. Poor resistance to corrosion
without alclad layer or secondary chem film, anodize and/or prime and paint. Can be chem film and anodized
readily. Other 2000 series alloys include 2017 seen widely in aluminum rivets, fasteners and screw machine
parts and 2014 which is used heavily in forgings. These three alloys, 2024, 2014, and 2017 can be
considered the foundations of aluminum aircraft, missiles and space vehicles during these past 75 years.