Characterization of High Strength Al-Zn-Mg Alloy Sheet for Hot Stamping

Abstract:

High formability is required to stamp aluminium into complex structural automotive components such as the A-pillar and B-pillar. Formability of an Al-Zn-Mg (AA7xxx) alloy sheet is characterised through hot stamping a prototype part and simulating paint baking procedures. The precipitation behaviour is assessed by differential scanning calorimetry and the tensile properties measured between 350°C and 475°C over a range of strain rates from 0.01s^-1 to 1s^-1. Natural ageing was found to increase the hardness of the hot stamped parts due to the formation of GP zone precipitates. A simulated three step paint baking procedure produced η precipitates and resulted in a yield strength and ultimate tensile strength of 480MPa and 512MPa, respectively.

• Periodical: Materials Science Forum (Volumes 794-796)
• Pages: 796-801
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.794-796.796
• Online since: June 2014
• Authors: Manoj Kumar*, Nikolay Sotirov, Christian Chimani
• Keywords: Al-Zn-Mg Alloy, DSC, Hot Forming, Precipitation Kinetics

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