INVESTIGATION OF THE INFLUENCE OF TEMPERATURE INCREASE ON THE STRUCTURAL STATE OF LOW-CARBON LOW-ALLOY STEEL

Abstract

\xa0Problem statement. The development and implementation of low-carbon low-alloy steels of high strength in the structural elements of blast furnaces, which will operate in conditions of heating to high temperatures is an urgent problem and can give a significant effect during the operation of buildings and structures.. Purpose of the article. establishing changes in the structural state of low-carbon low-alloy steels depending on the temperature rise. Conclusion. Conventionally, the temperatures at which the studied steels can be operated can be divided into two levels: the temperature below which no significant structural changes are detected; temperature at which significant structural changes are observed, which lead to a decrease in the reliability of structures. The presence of two levels associated with both the development of diffusion processes and the ability of the structural state to resist the effects of temperature stresses (structural stability). The structural stability of steel with increasing temperature is due to the processes that bring the system closer to the position of thermodynamic equilibrium compared to low temperature (structural state at room temperature), which is usually optimal in terms of performance. Such changes include the processes of recrystallization, coagulation of secretions and other phase transformations that lead to changes in the macro- and microstructure that impair the performance properties of the material. At relatively high temperatures, these processes occur at a significant rate, as a result of which they are crucial in limiting the possibility of using this material.