Modelling Yield Strength in an A6061 Aluminium Alloy

Abstract:

The yield strength of an A6061 Aluminium alloy for different artificial ageing times, strain rates and temperatures is modelled taking into account precipitation, solid solution and dislocation forest strengthening. Precipitation kinetics during artificial aging and the individual strength contributions are simulated with the thermokinetic software package MatCalc. In the present contribution, we introduce the model for the temperature and strain rate dependence of the yield-strength based on thermal activation theory. The experimental work presented here is performed on a Gleeble 1500 thermo-mechanical simulator, where the solution annealed and quenched samples are heat treated to produce materials in various microstructural conditions. We demonstrate that yield strength simulation is a powerful tool to reduce experimental effort and to cut down costs in the process of alloy engineering. This approach consistently represents the yielding behaviour of alloys in a variety of microstructural conditions with respect to the production history of the alloy and the testing conditions, i.e. temperature and strain rate.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 1014-1018
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.1014
• Online since: November 2016
• Authors: Johannes Kreyca*, Ahmad Falahati, Ernst Kozeschnik
• Keywords: A6061, Dislocation, Hardening, Precipitation, Yield Stress

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