1. Institute of Materials Engineering; Czestochowa University of Technology; Armii Krajowej 19 42-200 Czestochowa Poland
2. Institute for Ferrous Metallurgy; K. Miarki 12-14 44-100 Gliwice Poland
3. Faculty of Metals Engineering and Industrial Computer Science; University of Science and Technology; Mickiewicza 30 30-059 Cracow Poland