Duralumin is a trade name for one of the earliest types of age-hardenable aluminium–copper alloys. The term is a combination of Dürener and aluminium. Its use as a trade name is obsolete. Today the term mainly refers to aluminium-copper alloys, designated as the 2000 series by the international alloy designation system (IADS), as with 2014 and 2024 alloys used in airframe fabrication.
Fire-damaged Duralumin cross brace from the Zeppelin airship Hindenburg (DLZ129) salvaged from its crash site at Lakehurst Naval Air Station, NJ on May 6, 1937
Corrosion of duralumin
Duralumin sample from the 1931 airship USS Akron (ZRS-4)
The first mass-production aircraft to make extensive use of duralumin, the armored Junkers J.I sesquiplane of World War I
Aluminium–copper alloys (AlCu) are aluminium alloys that consist largely of aluminium (Al) and traces of copper (Cu) as the main alloying elements. Important grades also contain additives of magnesium, iron, nickel and silicon, often manganese is also included to increase strength. The main area of application is aircraft construction. The alloys have medium to high strength and can be age hardened. They are both wrought alloy. Also available as cast alloy. Their susceptibility to corrosion and their poor weldability are disadvantageous.
Fire-damaged Duralumin cross brace from the Zeppelin airship Hindenburg (DLZ129) salvaged from its crash site at Lakehurst Maxfield Field, NJ on May 6, 1937
Complete phase diagram
Corrosion of duralumin
Duralumin sample from the 1931 airship USS Akron (ZRS-4)