Combined grain boundary equilibrium and non-equilibrium segregation in ferritic/martensitic steels

This paper fulfils the need for a unified description of interfacial segregation in metallic solids. A model is developed which accounts for equilibrium and non-equilibrium segregation in a combined fashion. As a result it is possible to predict the amount of segregation to grain boundaries and other interfaces as a function of heat treatment variables like cooling rates and solution, ageing or tempering temperatures. The model's application to grain boundary segregation in ferritic/martensitic steel is described, and reasonable agreement between model predictions and observed segregation-based behaviour is demonstrated. The model is used to provide a set of rules which should be followed to alleviate harmful segregation for various elements in the steel.