# Peculiarities of diffusion in Cu-Fe and Co-Cu alloys

A. Khayrullin, S.N. Zhevnenko, A.O. Rodin

National University of Science and Technology “MISIS”, 119049, Leninsky pr. 4,
Moscow, Russia

Interest to the diffusion processes in Fe-Cu and Co-Cu systems is provoked by the
recent results: absence of advanced grain-boundary diffusion (GBD) [1,2]. The comparison of
the diffusion profiles obtained by electron probe microanalysis (EPMA) method near grain
boundaries and far from them (in the grain bulk) are the same. In order to avoid the additional
material transport associated with cutting and polishing, which can affect on concentration
profile the study on specially prepared foils is suggested. For such diffusion study the
additional preparation of samples after diffusion annealing is not required. Experiments were
performed on copper foils of thickness about 18 µm. Before the diffusion annealing the grain
boundaries were visualized by pre-annealing at high temperature due to Mullins' grooving.
The diffusant layer (Ni, Fe or Co) was deposited electrolytically. The accumulation of the
diffusing element on the opposite side during the diffusion annealing were measured. It was
shown that nickel penetrates and on the grain boundary and through the bulk, but the nickel
concentration near the grain boundaries is always higher than far from the boundaries

For samples with cobalt and iron the concentrations of these elements on the opposite
side were the same in the grain boundary and the bulk for all regimes of annealing.

1. A. A. Itckovich, B. S. Bokstein, A. O. Rodin, Mat. Lett. 135, 241 (2014).

2. D. S. Prokoshkina, A.O. Rodin, V. A. Esin, Phys. Metals Metallogr. 113, 583 (2012).

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