The high-strength aluminum alloys rely on age-hardening - a sequence of heat treatment steps that causes the precipitation of a nano-scale dispersion of intermetallics that impede dislocation motion and impart strength. This can be as high as 700 MPa giving them a strength-to-weight ratio exceeding even that of the strongest steels. This record describes for the series of wrought Al alloys that rely on age-hardening requiring a solution heat treatment followed by quenching and ageing. This is recorded by adding TX to the series number, where X is a number between 0 and 8 that records the state of heat treatment. They are listed below using the IADS designations (see Technical notes for details).2000 series - Al with 2 to 6% Cu -- the oldest and most widely used aerospace series.6000 series - Al with up to 1.2% Mg and 1.3% Si -- medium strength extrusions and forgings.7000 series - Al with up to 8% Zn and 3% Mg -- the Hercules of aluminum alloys, used for high strength aircraft structures, forgings and sheet. Certain special alloys also contain silver. So this record, like that for the non-age hardening alloys, is broad, encompassing all of these.

General Applications: 2000 and 7000 series - aerospace structures, pressure vessels, ultralight land-based transport systems; sports equipment such as golf clubs and bicycles. 6000 series - cladding and roofing; medium strength extrusions, forgings and welded structures for general engineering and automotive such as connecting rods.

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Record number: 1051