Properties of grain boundaries in BCC iron and iron-based alloys

The present report contains a summary of work done within the collaboration established between SCK•CEN and CIEA, performed during the internship of Xinfu He (CIAE) in the period of SEP 2009 – JUN 2010. In this work, we have carried out an atomistic study addressing the properties of grain boundaries in BCC Fe and Fe-Cr alloys. Throughout this work we report on the structural and cohesive properties of grain boundaries; thermal stability; interaction of grain boundaries with He and diffusivity of He in the core of the grain boundaries; equilibrium segregation of Cr near the grain boundary zone; cleavage fracture of grain boundaries; influence of the Cr precipitates, voids and He bubbles on the structure and strength of grain boundaries.