Materials Research Science and Engineering Center

 

Date of this Version

2006

Comments

Published in Mater. Res. Soc. Symp. Proc. Vol. 887. Copyright © 2006 Materials Research Society. Used by permission.

Abstract

Nanostructured materials are not immune from surface segregation, as can be shown for solid samples made from nanosized BaFe12-2xCoxTixO19 barium ferrite particles and a variety of free clusters. Both theory and experiment provide ample demonstration that very limited dimensions of very small clusters does not necessarily impart stability against surface and grain boundary segregation. In fact, with the larger surface to volume ratio in small clusters and lower average atomic coordination, we anticipate that compositional instabilities in small clusters will readily occur.