Thermally coupled combustion synthesis of composite ferroalloys

The results of a study of thermally coupled processes of self-propagating high-temperature synthesis (SHS) of composite ferroalloys are presented. It is shown that activation of the synthesis process by burning weakly exothermic systems based on ferroalloys is possible using various techniques. Namely, it can be realized by physical heating of the SHS charge in an electric furnace; mechanical activation of the exothermic charge; recovery of heat energy of synthesis; chemical heating of the SHS charge with termite additives and the use of a chemical oven. Various options of thermal stimulation for gas-free and filtration combustion synthesis with participation of ferroalloys, known as the metallurgical SHS process, are considered on the base of specific examples. Thermal activation of the gasless procedure of the metallurgical SHS process is considered on the example of the combustion of the ferroborontitanium system, and the filtration procedure – on the example of nitriding of low-carbon ferrochromium. The combustion products of ferroboron-titanium mixtures are considered as promising materials for steel microalloying with boron and titanium, and nitrided ferrochrome with low carbon content is one of the most demanded materials in melting of nitrogen-containing steels. The results of the studies carried out in this work have shown that the low exothermicity of the synthesis reactions of composite ferroalloys is not an obstacle to their implementation in the combustion mode. Well-known and new stimulation techniques for combustion synthesis allow to significantly expand the range of synthesized materials. Technological techniques such as heat energy recovery, mechanical activation of the exothermic charge, physical heating of the SHS charge in an electric furnace, chemical heating of the SHS charge with termite additives and the use of a chemical oven ensure the involvement of new raw materials with less exothermicity in the SHS process and carrying out of the process in milder conditions. This study was supported by the Tomsk State University Development Program (Priority-2030).