Computational Thermodynamics and Kinetics of Aluminum Nitride Precipitation in Steel—An Overview with Emphasis on Austenitic Grain Size Control

In various steel families, aluminum nitride plays an important role in the definition of steel behavior. It is now known that the effects are related to submicron particles, so it is not surprising that there was significant debate about the observed effects for a considerable time even as some of its benefits were already taken advantage of, in some steels. Currently, there is considerable knowledge and understanding of the effects of these particles and it is now possible, in many cases, to use computational thermodynamics to understand and properly tailor these effects. In the present work we briefly review how this knowledge developed and how the combination of thermodynamic and kinetic computational modeling makes it possible to take the most advantage of AlN in combination with the steel processing cycles. The results of the simulation examples presented should help engineers involved in alloy and process design and encourage the more extensive use of computational thermodynamic simulation in these design stages.