Hardening of Al-Mg-Si Alloys and Effective Particle Size in Microstructural Models

Abstract:

It is well established that the precipitate volume fraction and size are the dominating parameters determining the hardening in Al-Mg-Si alloys. Several empirical models of the relationship between precipitate morphology and hardening have been published, but the coherency strain field surrounding the particles has so far not been taken into account. The authors have earlier published data with characterisation of microstructure of aged Al-Mg-Si alloys, including estimation of the coherency strain field surrounding these (semi-) coherent precipitates. In this paper the effect of including the coherency strain field as part of the effective hardening diameter of the precipitates in hardening models is evaluated. The correlation between the tensile test results and mechanical properties calculated with an appropriate microstructural model increased from 0.78 to 0.87, by implementation of coherency strain field as part of the effective particle radius in the model.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 252-257
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.252
• Online since: May 2014
• Authors: Sverre Gulbrandsen-Dahl*, Knut Marthinsen
• Keywords: Al-Mg-Si Alloy, Artificial Aging, Mechanical Property, Precipitation

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