Abstract
Several research results suggest the binding energy of carbon-vacancy (C-V) complexes is of the order 35-55 kJ/mole in face-centered cubic (fcc) iron-base alloys. In addition to point-defect anelasticity, we examine data on self-diffusion of Fe in fcc Fe, which are quantitatively consistent with our results on point-defect structure modeling. Quenching, cold work, and electron irradiation increase the height of damping peaks associated with C motion, consistent with a contribution of C-V complexes to the relaxation strength of these peaks. The effect of increasing C content on self-diffusion of Fe in fcc Fe is to decrease the activation energy for self-diffusion, hence increase the diffusivity, and implies a C-V binding energy of ∼40 kJ/mol. We have used first-principles gradient-corrected density functional calculations to determine directly the binding energy of nearest-neighbor C-V pairs in fcc iron. A value of ∼35 kJ/mol is obtained.
Original language | English (US) |
---|---|
Pages (from-to) | 67-72 |
Number of pages | 6 |
Journal | Materials Science and Engineering A |
Volume | 370 |
Issue number | 1-2 |
DOIs | |
State | Published - Apr 15 2004 |
Keywords
- Anelasticity
- Austenitic alloys
- Carbon-vacancy binding
- Point defects
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering