The group deals with studies of the electronic structure, short range atomic order and strengthening mechanisms in iron-
Main scientific results:
(i) A correlation is found between the electronic structure (state density at the Fermi surface) and short-
(ii) It is shown that nitrogen increases the concentration of free electrons in austenitic steels and, based on this result, the beneficial nitrogen effects in steel are explained, such as: increased thermodynamic stability of solid solutions, high fracture toughness, high strengthening due to cold work and low temperatures, increased strengthening by grain boundaries etc. Main results are summarized in the monography V. Gavriljuk, H. Berns, High Nitrogen Steels, Springer, Berlin (1999).
(iii) It is found that combined alloying of steels with nitrogen+carbon is promising in terms of the increased thermodynamic stability of solid solutions, which suggests a unique possibility for design of cost-
Ruhr University, Bochum, Germany, Chair of materials technology (Prof. Dr. emeritus H. Berns, Prof. W. Theisen), Chair of materials properties (Prof. Dr. M. Pohl);
Lille University of Sciences and Technologies, Lille, France, Laboratory of physical metallurgy and engineering materials (Prof. J. Foct);
Albany Research Centre, Albany, Oregon, U.S.A. (Dr. J. Rawers).
Tyshchenko Andriy, team Leader