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Precipitation Kinetics of the Hardening Phase in Two 6061 Aluminium Alloys


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Abstract


The purpose of this work is to study the kinetics of the precipitation of the hardening phase in two commercial age-hardenable Al–Mg–Si alloys. A review of the theoretical framework for solid-state reactions kinetics and the determination of kinetic parameters from DSC curves is provided, then used to quantify β" precipitation in the two alloys studied. Despite failure to achieve high levels of accuracy, due, in particular, to the dilution of the alloys, the procedure to analyse this precipitation reaction yields valuable results. It is established that β" precipitates homogenously as needles which grow through an enhanced-diffusion mechanism.
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Keywords


Activation Energy; Aluminium Alloys; β" Phase; Precipitation; Reactions Kinetics

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