Experimental and numerical analysis about the cyclic behavior of the 304L and 316L stainless steels at 350 °C Lakhdar Taleb a,⇑ , Georges Cailletaud b , Kacem Saï c a INSA, GPM, CNRS UMR 6634, BP 08 avenue de l’université, 76801 St. Etienne du Rouvray Cedex, France b MINES ParisTech, Centre des Matériaux, CNRS UMR 7633, BP 87, 91003 Evry Cedex, France c UGPMM Ecole nationale d’ingénieurs de Sfax, B.P. 1173, Sfax, Tunisia article info Article history: Received 11 December 2013 Received in final revised form 7 May 2014 Available online 9 June 2014 Keywords: A. Fatigue B. Cyclic loading B. Elastic-plastic material B. Metallic material Ratcheting abstract In a previous study, we have demonstrated that cyclic accumulation of the inelastic strain exhibited by 304L SS at room temperature under tension–compression stress control is mostly due to creep (Taleb and Cailletaud, 2011). The same result in the same conditions is pointed out for 316L SS (Taleb, 2013a). In the present paper, the cyclic behavior of both 304L and 316L stainless steels at 350 °C is investigated. Creep is not significant at this tem- perature. In addition to tension–compression tests, the effect of non-proportional loading paths (axial-torsion) is considered for both stress and strain controlled conditions. The study suggests that ratcheting is very small with the different mean stress and amplitude used remaining into the assumption of small strains; this observation may be linked to the large cyclic hardening exhibited by both materials. However ratcheting seems more important under non-proportional loading path compared to the equivalent tension– compression conditions. A multi-mechanism model has been used to simulate the whole experimental data base. After the identification process of the material parameters con- ducted by considering only strain controlled experiments, its predictive capabilities have been evaluated on the stress controlled tests. The model presents a very good quantitative agreement with the quasi absence of ratcheting. However, the model fails in describing the over-hardening (mostly isotropic) observed under monotonic loading when the maximum strain is large (about 4%). Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction The cyclic behavior of metallic alloys has been extensively investigated during the last decade, in one-dimensional or more complex conditions for different classes of materials. Specifically, austenitic stainless steels have retained the attention of researchers, due to their complex cyclic behavior. Ratcheting combined with cyclic hardening can be observed under pro- portional and non-proportional loading paths (Abdel Karim, 2010; Bari and Hassan, 2002; Bocher et al., 2001; Hassan et al., 2008; Jiang and Zhang, 2008; Kang et al., 2004; McDowell, 1987; Moosbrugger, 1993, etc.). The strain memory effect (Belattar et al., 2012; Chaboche, 2008; Chaboche et al., 1979; Nouailhas et al., 1985; Ohno, 1982; Taheri et al., 2011, etc.) introduces a strong influence of the loading history on hardening. The interaction between creep and ratcheting has also been evaluated at room temperature since a long time (Krempl, 1979, 1990; Yoshida, 1990, etc.). Nevertheless, the process is not well understood yet. It has been recently demonstrated that the cyclic http://dx.doi.org/10.1016/j.ijplas.2014.05.006 0749-6419/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +33 2 32 95 97 65; fax: +33 2 32 95 97 10. E-mail addresses: lakhdar.taleb@insa-rouen.fr (L. Taleb), Georges.Cailletaud@ensmp.fr (G. Cailletaud), kacemsai@yahoo.fr (K. Saï). International Journal of Plasticity 61 (2014) 32–48 Contents lists available at ScienceDirect International Journal of Plasticity journal homepage: www.elsevier.com/locate/ijplas