Дифузійна модель розпаду аустеніту в леґованій сталі з урахуванням його стабілізації

The diffusion model of the austenite transformation in hypoeutectoid alloyed steel during isothermal holding is received further development. The model which is developed provides ability to determine the volume fraction of the structural components, the quantity of which are depends on the magnitude of the steel overcooling. The model is considers the degree of the overcooling of austenite, the contents of carbon and structural components in the steel, the size of the nucleus, the volume fraction of the phases, the quantity of the carbon, which are running through a unit area over a period of time, the balance of thermal energy, etc. As shown, in the hypoeutectoid alloyed steel there are two maximum of the austenite stability in the temperature ranges of the existence of upper and lower bainite. The amount of retained austenite is minimal between these temperature diapasons. As established, the residual austenite, depending on the value of the steel overcooling and the temperature range of the holding during subsequent cooling, can decompose by diffusion or shear mechanisms. [ABSTRACT FROM AUTHOR]