Atomic-scale observations of two-dimensional Re segregation at an internal interface in W(Re)

Abstract

Equilibrium Re segregation is studied at a grain boundary in a single-phase W--25-at. %-Re alloy employing atom-probe field-ion microscopy. The grain-boundary concentration is measured, without data deconvolution, to be 73.8\ifmmode\pm\else\textpm\fi{}5.45 at. % Re at an interface plane. This is the first direct proof that segregation at a grain boundary can be purely two dimensional, and that it can occur at a so-called low-energy interface.