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Abstract: This work is devoted to the preparation of ultrafine material based on Al–Cu–Fe quasicrystalline phase by powder metallurgy using mechanical alloying and Spark Plasma Sintering. The dependence of microstructure and phase composition of powders on the conditions of mechanical alloying was described. It was found that the Al60Cu30Fe10 quasicrystalline phase forms directly already after 2 h of milling under optimized conditions. The stability of this quasicrystalline phase was studied at various temperatures of Spark Plasma Sintering compaction process. [Copyright &y& Elsevier]

The structure of Ni 8 Ti 5 was solved and refined from precession electron diffraction tomography data using dynamical refinement approach. It has trigonal symmetry R -3 m ( a = 12.24(5) Å, c = 15.33(5) Å) with a structure related to the structure of Ni 4 Ti 3 . The greatest challenge of the structure determination was the assignment of atomic types due to the proximity of scattering powers of Ti and Ni. Several approaches to determination of atom type distribution over atomic positions were used; (1) analysis of the Wyckoff position multiplicities, (2) refinement of displacement parameters, and (3) geometrical analysis of the structure and comparison with known structures. These approaches consistently pointed to one distribution, which was confirmed by a significant improvement of the refinement figures of merit. [ABSTRACT FROM AUTHOR]