ДОСЛІДЖЕННЯ МЕХАНІЗМІВ РУЙНУВАННЯ ПЕРИКЛАЗОВУГЛЕЦЕВИХ ВОГНЕТРИВІВ У СКЛАДІ ФУТЕРІВКИ 60-Т КИСНЕВОГО КОНВЕРТЕРА МЕТОДАМИ МІКРОСТРУКТУРНОГО АНАЛІЗУ

Анотація

The main task of refractory lining in oxygen converters is the isolation of the metal elements of the unit from the high-temperature reaction bath of the converter. At the same time, it is affected by various extreme factors that are different in nature. The wear of refractory products in oxygen converters depends on both the quality of the refractory units themselves and the used technology of steel smelting. The study examined the possible causes of the destruction of the periclase-carbon lining of an industrial oxygen converter with a capacity of 60 tons during the campaign of 2002 heats. The research methodology involved the selection of samples from different areas of the refractory lining of the oxygen converter before operation and after the end of the full company. Obtained samples were tested by methods of microstructural analysis for detection of characteristic structural changes to establish patterns and mechanisms of destruction. Samples for analysis were taken from the area of the metal bath (the area of the lining, mainly in contact with the metal melt), from the cylindrical part (preferably in contact with the slag phase) and helmet part (preferably in contact with the oxidizing gas phase). The results of microstructural analysis of refractory samples taken from different parts of the converter lining after the campaign, compared with similar samples taken before the campaign, indicated the following: the formation of grains in the periclase of the lining and its subsequent destruction within the grain boundaries the emergence of various stresses (thermal, dynamic) that cause cyclical deformations. This feature is characteristic of samples taken from all areas of the lining, and the most characteristic of this aspect was observed in samples of refractory materials taken from the cylindrical part of the lining.