A plasticity model with yield surface distortion for non proportional loading

Abstract

International audienceIn order to enhance the modeling of metallic materials behavior in non proportional loadings, a modification of the classical elastic-plastic models including distortion of the yield surface is proposed. The new yield criterion uses the same norm as in the classical von Mises based criteria, and a "distorted stress" Sd replacing the usual stress deviator S. The obtained yield surface is then “egg-shaped” similar to those experimentally observed and depends on only one new material parameter. The theory is built in such a way as to recover the classical one for proportional loading. An identification procedure is proposed to obtain the material parameters. Simulations and experiments are compared for a 2024 T4 aluminum alloy for both proportional and nonproportional tension-torsion loading paths

Strain-path change induced transients in flow stress, work hardening and r-values in aluminum

“…One group of models tries to modify the shape of the yield locus, i.e. by changing the tensor by either rotating or distorting it (Baltov and Sawczuk, 1965;Barlat et al, 2011;Barlat et al, 2013;Barthel et al, 2008;Choi et al, 2006;Feigenbaum and Dafalias, 2007;Francois, 2001;Ishikawa, 1997;Ishikawa and Sasaki, 1998;Levkovitch and Svendsen, 2007b, a;Noman et al, 2010;Pietryga et al, 2012). The yield surface distortion during both proportional and non-proportional strain paths was also observed experimentally (Khan et al, 2009;Khan et al, 2010a, b;Pandey et al, 2013).…”

Dimensional stability of materials subject to random vibration

“…10, for a low strain range. The second was from a study by Francois [22] for a similar material (alloy 2024 T4) in a relatively high range of plastic strain. The constants used are given in Table 3.…”

Capturing yield surface evolution with a multilinear anisotropic kinematic hardening model

“…Some of the models are phenomenological Miller, 1987, 1988;Kurtyka and Zyczkowski, 1996;Voyiadjis and Foroozesh, 1990;Francois, 2001;Liu et al, 2011;Wu and Hong, 2011;Lee et al, 2012;Radi and Abdul-Latif, 2012;Barlat et al, 2013;Shi et al (2014)) and some of http://dx.doi.Org/10.1016/j.ijsolstr.2015.ll.030 0020-7683/© 2015 Elsevier Ltd. All rights reserved. them micromechanically-based or motivated (Zattarin et al, 2004;Kabirian and Khan, 2015;Yoshida et al, 2014;Hu et al, 2015).…”