The Diffusion Coefficients Of Cu And Zn In Α- And Η- Solid Solutions
Adhurim Hoxha, Joan Jani
Index Terms: Multiphase diffusion, Platting technique, Diffusion coefficients, Intermetalic phases, Activation energies, Frequency factor, EPMA.
Abstract: In this work, the multiphase diffusion in the infinite couple Cu-Zn, was studied experimentally. The diffusion couples were prepared by platting technique. The samples were annealed in three different temperatures, which were taken below the melting temperature of Zn. For each temperature, there were used six different annealing times, ranging from 1h up to 32h. In the micrographs provided by light microscopy, it can be seen the formation of only two of the three intermetalic phases present in the Cu-Zn phase diagram, namely ε- and γ-phase. WDX EPMA analysis was used to obtain the concentration profiles of the diffusion layers.he diffusion coefficients of Cu and Zn in α- and η-solid solutions, are calculated using the solutions of second Fick’s law, for independent concentration case. Since the diffusion coefficients depends only on the temperature of annealing and not on the time of it, they must be the same for a given temperature. Therefore the diffusion coefficients were averaged for each temperature. Knowing the diffusion coefficients for each temperature, enables the calculation of the activation energies and the frequency factors as well.
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