ε-Carbide in alloy steels: First-principles assessment

There is now a large number of sophisticated steels which rely on silicon as an alloying addition with the purpose of avoiding the precipitation of cementite. However, there is also evidence that the silicon can enhance the formation of epsilon-carbide; the mechanism of this effect is not understood and the absence of appropriate thermodynamic data makes it impossible to conduct calculations. We report here some ab initio calculations which throw light on both of these issues and suggest novel experiments. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.