Local values of the diffusivities at the migration front of the discontinuous precipitates in Al-22 at.% Zn alloy
- Polish Academy of Sciences, Cracow (Poland)
- Univ. Stuttgart (Germany). Inst. fuer Metallkunde
Diffusion along migrating grain boundaries is a rate-controlling factor in many solid-solid phase transformations like discontinuous precipitation (DP), discontinuous dissolution (DD) and diffusion-induced grain boundary migration. In this paper it will be shown that some divergence between the tracer diffusivities obtained by the sectioning technique and the chemical diffusivity data obtained from DP and DD processes can be removed by applying a local concept for the determination of the kinetic parameters for these reactions. It means that the solute concentration in the {alpha} solution will be measured for the same individual cell whose solute profile across the {alpha} lamella was determined in the former DP process. An Al-22 at.% Zn alloy was chosen for the investigation for which reliable data for the tracer diffusivity of stationary grain boundaries of Al-Zn solid solutions over a wide range of zinc content were previously reported. As the DP and DD reactions are also well documented, the Al-Zn system is particularly useful for studies of the mutual relation between the diffusivities of stationary and moving grain boundaries.
- OSTI ID:
- 642133
- Journal Information:
- Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 1 Vol. 39; ISSN 1359-6462; ISSN SCMAF7
- Country of Publication:
- United States
- Language:
- English
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