Effect of Precipitation Behavior on Mechanical Properties of 6082 Aluminum Alloy

The mechanical properties of 6082 aluminum alloy under different aging conditions were investigated in this study. Precipitation behavior leading to an increase in strength was confirmed by the observation of the microstructure using TEM. The β″ precipitate, which is coherent with the Al matrix, contributes to the high tensile strength and hardness of the alloy. The transformation of the β″ phase into the β′ phase observed under TEM was proven to be responsible for the decrease in strength and hardness. The hardness curves indirectly reveal that a higher aging temperature could accelerate the transformation of β″ into β′. The coherent strain field introduced by the β″ precipitate was clearly observed and is discussed. In addition, an ideal artificial aging window is proposed, with a combined performance of a TS of 360 MPa, hardness of 105 HB and elongation over 10%.