A set of open-system elastic constants used to approximate the redistribution of interstitial atoms among the three different interstitial sublattices in a body-centered cubic (bcc) metal is derived accounting for the tetragonal nature of the compositional strain in the presence of a nonhydrostatic stress. Predictions of the stress-induced composition change are calculated and compared to the actual solution and to two other approximation schemes, one based on a hydrostatic compositional strain and one based on ignoring the compositional self-stress. The open-system elastic constants give a qualitatively and quantitatively accurate representation of the composition changes when the far-field composition is greater than a few percent. For very small far-field compositions, less than about 10-4, the compositional self-stress can be ignored in calculating the stress-induced interstitial redistribution. However, for larger far-field compositions, neglecting the compositional self-stress can overestimate significantly the degree of interstitial redistribution.
|Number of pages||7|
|Journal||Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science|
|Publication status||Published - 2003 Dec|
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys