The diffusion behavior of bgr; phase Cundash;Al has been studied at 800, 850, and 950thinsp;deg;C using the experimental approach and analysis scheme of Kirkendall and Darken. Diffusion couples were made using the window frame technique and concentration profiles were determined by electron probe microanalysis. The chemical diffusion coefficient,Dtilde; was found to beDtilde;=0.65thinsp;exp(minus;42200/RT) cm2/s. The diffusivity was observed to be independent of composition over the range 11ndash;13 wt.thinsp;percnt; Al. The selfhyphen;diffusion coefficientsDCuandDAlwere determined to beDAl=0.13thinsp;exp(minus;38900/RT) cm2/s andDCu=2.2thinsp;exp(minus;43400/RT) cm2/s. All activation energies are in calories/mole.
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