Abstract: An ageing process capable of producing an aluminum alloy with better mechanical properties than possible with traditional ageing procedures. The ageing process employs a dual rate heating technique that comprises a first stage in which the aluminum alloy is heated at a first heating rate to a temperature between 100 and 170° C. and a second stage in which the aluminum alloy is heated at a second heating rate to a hold temperature of 160 to 220° C. The first heating rate is at least 100° C./hour and the second heating rate is 5 to 50° C./hour. The entire ageing process is performed in a time of 3 to 24 hours.

Abstract: An aluminum alloy and a process for treating the aluminum alloy. The alloy contains 0.5 to 2.5% by weight of an alloying mixture of magnesium and silicon, in which the molar ratio of Mg/Si is 0.70 to 1.25, the alloy optionally containing an additional amount of silicon up to about ⅓ of any iron, manganese and chromium in the alloy, as expressed by weight percent, the balance of the alloy being aluminum, optional alloying elements and unavoidable impurities. The process entails an ageing technique that includes a first stage in which an extrusion of the aluminum alloy is heated at a rate above 100° C./hour to 100-170° C., a second stage in which the extrusion is heated at a rate of 5 to 50° C./hour to a final hold temperature, wherein the total ageing operation is performed in 3 to 24 hours.