Deformation-induced non-equilibrium grain boundary segregation in dilute alloys

✍ Scribed by S.-H. Song; Q. Zhang; L.-Q. Weng

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 370 KB
• Volume: 473
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2007.04.007

✦ Synopsis

On the basis of the vacancy-solute complex mechanism, a model describing deformation-induced non-equilibrium grain boundary segregation of solute is established for dilute alloys, which includes the quasi-thermodynamics and kinetics. The model is applied to the evaluation of non-equilibrium grain boundary segregation of boron during high temperature plastic deformation in an austenitic steel microstructure. The deformation-induced non-equilibrium segregation increases with decreasing temperature and is considerably larger than the thermal equilibrium one, especially in the temperature range below ∼750 • C. In addition, at a given temperature the non-equilibrium segregation augments with rising strain rate as the deformation-created supersaturated vacancy concentration increases. The predictions are generally consistent with some experimental observations.