INTERATOMIC FORCES AND ATOMIC-STRUCTURE OF GRAIN-BOUNDARIES IN COPPER-BISMUTH ALLOYS.

Yan M., Sob M., Luzzi D. E., Vitek V., Ackland G. J., Methfessel M., Rodriguez C. O.

Univ Penn Dept Mat Sci & Engn Philadelphia Pa 19104
Univ Edinburgh Dept Phys Edinburgh Eh9 3jz Midlothian Scotland
Max Planck Inst Festkorperforsch W-7000 Stuttgart 1 Germany

The many-body empirical potentials that describe atomic interactions in the copper-bismuth system were constructed using both experimental data and physical quantities obtained by ab initio full-potential linear muffin-tin orbital calculations for a metastable Cu3Bi compound. These potentials were then used to calculate the structure of a grain boundary in copper containing bismuth, which was at the same time studied by high-resolution electron microscopy (HREM). Excellent agreement between the calculated and observed structures is shown by comparing a through-focal series of observed and calculated images. This agreement validates the constructed potentials, which can be used with a high confidence to investigate the structure and properties of other grain boundaries in this alloy system. Furthermore, this study shows, that HREM combined with computer modeling employing realistic empirical potentials can decipher with great accuracy the structure of boundaries containing multiple atomic species.
 

Physical Review B, 47 5571-5582, 1993.


Max-Planck Institut für Festkörperforschung;
Postfach 80 06 65   D-70506 Stuttgart