Abstract
We have investigated interdiffusion in iron-aluminium alloys using single-phase interdiffusion couples of FexA\1-x-Fe yA\1-y for three combinations of x and y for Al contents between 18 and 49.5 at. % Al. Experimental diffusion profiles were obtained from electron-microprobe analysis of the diffusion zone. Interdiffusion coefficients were deduced via the Sauer-Preise method taking into account volume changes. A temperature interval between 997 and 1447 K was covered in our experiments. Thermodynamic factors were obtained from two theoretical models and judged by an analysis of the Kirkendall effect in the diffusion couples. The Darken-Manning equation was used to deduce self-diffusion coefficients of aluminium from the present interdiffusion coefficients, the thermodynamic factors, the vacancy-wind factors, and the iron tracer diffusivities obtained recently at the Münster laboratory. The results show that Al diffusion is always slightly faster than Fe diffusion. The difference never exceeds a factor of three. This small difference indicates that Fe and Al diffusion in B2 ordered iron-aluminides are closely coupled.
Original language | English |
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Pages (from-to) | 444-449 |
Number of pages | 6 |
Journal | Defect and Diffusion Forum |
Volume | 237-240 |
Issue number | PART 1 |
DOIs | |
State | Published - 1 Jan 2005 |
Keywords
- Darken-Manning equation
- Interdiffusion
- Iron-aluminides
- Self-diffusion of Al
- Thermodynamic factor
- Vacancy-wind factor
ASJC Scopus subject areas
- Radiation
- General Materials Science
- Condensed Matter Physics