Issue 30

V. Anes et alii, Frattura ed Integrità Strutturale, 30 (2014) 282-292; DOI: 10.3221/IGF-ESIS.30.35

Figure 8 : Numeric cyclic behavior comparison between the numeric model developed and the Jiang & Sehitoglu plasticity model for 1.4% as axial strain reference PT, PS, PP and OP. a) b) c) d)

C ONCLUSIONS

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n this paper was studied the elastic-plastic mechanical behaviour of a magnesium alloy (AZ31B-F) through experimental tests under uniaxial loading conditions. The particular mechanical behaviour inherent to these kinds of materials, hexagonal closed pack microstructures, leads to conclude that it is necessary to have a numeric elastic plastic model implemented through experimental data. In this context is presented here a first iteration for a numerical model, which modulates the several physical mechanisms inherent to the magnesium elastic-plastic behaviour in uniaxial loading conditions. In order to validate the work already done, numeric estimations were compared with the uniaxial data and with the Jiang & Sehitoglu plasticity model. The numeric results from the implemented model were acceptable; however the Jiang & Sehitoglu model shows some shortcomings on the magnesium hysteresis loop estimations. A CKNOWLEDGEMENTS he authors gratefully acknowledge financial support from FCT – Fundação para a Ciência e Tecnologia (Portuguese Foundation for Science and Technology), through the project PTDC/EME-PME/104404/2008.

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R EFERENCES

[1] Sonsino, C.M., Dieterich, K., Fatigue design with cast magnesium alloys under constant and variable amplitude loading, International journal of fatigue, 28 (2006) 183–193. [2] Anes, V., Reis, L., Li, B., Fonte, M., de Freitas, M., New approach for analysis of complex multiaxial loading paths, International Journal of Fatigue, 62 (2013) 21-33.

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