| Numéro |
J. Phys. Colloques
Volume 49, Numéro C5, Octobre 1988
Interface Science and Engineering '87An International Conference on the Structure and Properties of Internal Interfaces |
|
|---|---|---|
| Page(s) | C5-557 - C5-562 | |
| DOI | https://doi.org/10.1051/jphyscol:1988568 | |
Interface Science and Engineering '87
An International Conference on the Structure and Properties of Internal Interfaces
J. Phys. Colloques 49 (1988) C5-557-C5-562
DOI: 10.1051/jphyscol:1988568
Department of Materials Science and Engineering, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 227, Japan
An International Conference on the Structure and Properties of Internal Interfaces
J. Phys. Colloques 49 (1988) C5-557-C5-562
DOI: 10.1051/jphyscol:1988568
ELECTRONIC THEORY FOR GRAIN BOUNDARY SEGREGATION AND EMBRITTLEMENT OF INTERMETALLIC COMPOUND Ni3Al
K. MASUDA-JINDODepartment of Materials Science and Engineering, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 227, Japan
Abstract
The cleavage strength of grain boundaries in L12 type of intermetallic compounds (Ni3Al) is investigated using the tight-binding (TB) electronic theory of s, p and d-basis orbitals. The two center hopping integrals are determined by using the Harrison's universal TB theory and atomic energy levels are taken from the atomic structure calculations by Herman and Skillman. The local charge neutrality condition is used for both host metal and solute atoms. It is shown that cleavage strength of the grain boundaries depends strongly on the segregation of impurity atoms (boron) at the grain boundaries, in agreement with experimental results : The stoichiometry effect of the L12 compound is also discussed.