1. Department of Materials, Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića Street No. 1, HR10000 Zagreb, Croatia (Corresponding author), e-mail; sasa.kovacic@fsb.hr
2. Department of Materials, Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lučića Street No. 1, HR10000, Zagreb, Croatia