Pomarin Y. Investigation of high-temperature processes of interaction of nitrogen with melts and development of a method for alloying of steels with nitrogen during arc-slag-remelting

The thesis is dedicated to high-temperature investigations into thermodynamics and kinetics of interaction of nitrogen with molten metals and alloys, and development of a technology and equipment for arcslag remelting of steels combined with nitrogen alloying directly from the gas phase.Presented is the phenomenological description of the ASR process occurring in the atmosphere of nitrogen under surplus and increased pressures, where the arc burns between a consumable electrode and slag which fully or partially covers the metal pool. Electrical characteristics of the arc discharge during ASR were studied. It is shown that the presence of easily ionized elements in slag causes a drastic decrease in voltage gradient in the arc column. Pioneering systematic investigations were conducted to study thermodynamics and kinetics of absorption of nitrogen by the melts within a wide range of temperatures, pressures and concentrations of alloying elements.