Issue 37

J. Kramberger et alii, Frattura ed Integrità Strutturale, 37 (2016) 153-159; DOI: 10.3221/IGF-ESIS.37.21 153 Focussed on Multiaxial Fatigue and Fracture Computational simulation of biaxial fatigue behaviour of lotus-type porous material J. Kramberger, M. Šori University of Maribor, Faculty of mechanical engineering, Smetanova 17, 2000 Maribor, Slovenia janez.kramberger@um.si marko.sori@um.si M. Šraml University of Maribor, Faculty of civil engineering, transportation engineering and architecture, Smetanova 17, 2000 Maribor, Slovenia matjaz.sraml@um.si S. Glodež University of Maribor, Faculty of mechanical engineering, Smetanova 17, 2000 Maribor, Slovenia srecko.glodez@um.si A BSTRACT . A computational simulation of low-cycle fatigue behaviour of lotus-type porous material, subjected to biaxial in-phase loading cycles is presented in this paper. Fatigue properties of porous materials are less frequently published in the literature. This paper evaluates computational analyses, where different pore distribution and biaxial loading conditions in relation to the pore orientations is considered in each simulation. The fatigue analysis is performed by using a damage initiation and evolution law based on the inelastic strain energy. The computational results are subjected to the appropriate statistical analysis, because of different pore topology a different fatigue lives are obtained on the same loading level. Results of computational simulations show also a qualitative understanding of porosity influence on low-cycle fatigue failures of lotus-type porous material under biaxial loading conditions. K EYWORDS . Lotus-type porous material; Low-cycle fatigue; Damage; Finite element analysis. I NTRODUCTION orous materials are relatively new class of materials, which offer potential for lightweight structures, energy absorption and other applications [1-3]. Current manufacturing methods enable to create various porous materials, either open-celled or closed-celled porous structures with varying pore morphology. A new type of porous material with unidirectional cylindrical pores is Lotus-type porous material, which is often used in lightweight structures, medicine, automotive engineering, sports equipment, etc. [4]. The porosity of lotus materials is usually lower than porosity of some conventional porous metals [5]. P