Improvement in Bake Hardening Response of Al-Si-Mg Alloys

Response to artificial ageing of dendritic and globular Al–7Si–Mg alloys

“…The additional signals superimposed on the DSC scan of alloy A when alloys B and C are thermally exposed, make their respective DSC scans look a lot like those of excess-Si wrought Al-Mg-Si alloys. The precipitation sequence of the latter is established to be, SSS → clusters → GP-I zones → ␤ → ␤ + Si → ␤ where SSS is the supersaturated aluminium solid solution [6,[16][17][18][19][20][21][22][23]. The precipitation sequence of alloys B and C is expected to be nearly the same possibly with a more pronounced Si precipitation activity.…”

Effect of cooling rate on precipitation during homogenization cooling in an excess silicon AlMgSi alloy

“…8. The DSC spectrum of the EN AW 6082 sample quenched directly at the end of soaking reveals the full precipitation sequence owing to a supersaturated matrix, which is well established in AlMgSi alloys to be SSSS → GP zones→ β″ →β′ → Si → β [19][20][21][22][23][24][25][26][27]. Hence, the first weak exothermic signal centering at approximately 160°C is assigned to the formation of GP zones while the following weak endothermic signal to their dissolution.…”

Bake hardening of twin roll cast Al–Mg–Si sheet

“…Age hardenable Al-Mg-Si alloys have become the materials of choice for skin panel applications owing to a remarkable strengthening potential during the paint bake cycle. [1][2][3][4][5] The age hardening potential of these alloys, however, cannot be fully exploited in paint bake cycles at automobile plants owing to the low temperatures and short times involved. [6][7][8] Besides, the body panel sheet is often stored for quite some time and undergoes natural aging before it is finally stamped at the automobile plant.…”