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Information × Registration Number 0305U003271, 0103U004217 , R & D reports Title Transport processes in the quasi-crystals Ti-Zr-Ni with hydrogen popup.stage_title Механічні властивості та електричний опір квазікристалів Ti-Zr-Ni. Ізотопічний ефект при дифузії водню у цих матеріалах. Head Merisov B., Khadzhaj G., Registration Date 04-03-2005 Organization Kharkov national university named after V.N. Karazin popup.description2 The mechanical characteristics and electrical resistivity of the Ti-Zr-N quasicrystals. Objects - icosahedral quasicrystals Тi41.5Zr41.5Ni17. Methods: nanoindentation, the electrical resistivity measurements, X-ray diffraction. The purpose of work: the study of the particularities of plastic behaviour of Ti-Zr-Ni quasicrystals under nanoindentation, the building of the qualitative (phenomenоlogical) physical model of of the process of deformation of quasicrystals in contrast with monocrystals; the study of particularities of the electrical resistivity at low temperature, including influence of magnetic fields on the superconducting transition. It is adduced the comparative analysis of parameters and mechanisms of deformation of the Ti41.5Zr41.5Ni17 quasicrystal and the W+12%Ta monocrystal at the nanoindentation. It is stated that, unlike crystal, there is not the purely elastic area on the deformation curve of quasicrystal, and beginning with some critical value of load, the plastic deformation has thestep-like character with alternation of slow elastic-plastic and quick plastic deformation areas. The size of quick plastic deformation areas (from 4 to 6 nm) is greatly smaller than the coherence length (from 15 to 40 nm) so the revealled effects characterize the mechanisms of mono-quasicrystal deformation. It is offered the qualitative model of the plastic deformation of quasicrystals under nanoindentation. It is studied the electrical resistivity of the icosahedral quasicrystals Ti41.5Zr41.5Ni17 in the temperature region 0.3-300 K on samples of different quality. In the field 0.3-2 K it is studied the influence of external magnetic fields up to 1.6 Тl on the superconducting transition in these material. The temperature dependency of resistivity in the superconducting transition region is step-like. The X-ray data shows the presence of the different quasicrystal phases in samples. Above the superconducting transition it is found the minimum of electrical resistivity. Branch - solid state physics. Product Description popup.authors popup.nrat_date 2020-04-02 Close