Triple junction segregation in nanocrystalline multilayers

Stender P., Balogh Z., Schmitz G.

Zusammenfassung

Triple junctions (TJ’s), topologically required linear defects of grain boundary structure, are suggested tocontrol the behavior of nanocrystalline material. However, measurements of their properties are rare. With atomprobe tomography, reliable analysis of singular features of the grain boundary structure becomes possible. Wereport microscopic measurements of segregation along individual TJ’s in Fe/Cr. By segregation to TJ’s nanometrictubular objects of distinct properties are formed. The determined segregation enthalpy of 0.076 eV indicates thatTJ’s provide considerable free volume similar to free surfaces.