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Information × Registration Number 0209U006081, 0106U003115 , R & D reports Title Research of relaxation processes in conditions of plastic and superplastic deformation of polycrystalline samples popup.stage_title Head Sirenko Anatoliy Fedotovich, Registration Date 21-01-2009 Organization Kharkov Natuional university named after V.N.Karazin popup.description2 The objects of research are two-dimensional polycrystals of aluminium and samples with the hardening coating of titanium nitride, eutectic alloy Pb-62%Sn. The purpose of research work is finding the mechanisms of transcrystalline and grain boundary failure under the plastic deformation of two-dimensional polycrystals of aluminium, a determination of the essence of structural and phase transitions that are taking place at different stages of deformation of superplastic alloys. The methods of research are: mechanical tests under the conditions of creep and active loading, scanning electron and optical microscopy, X-ray structure analy-sis and original methods of investigations in situ of structural changes attended plas-tic deformation of samples. There was determined for the first time the regularity of orientation and struc-tural changes that precede appearing of the transcrystalline cracks during plastic de-formation of two-dimensional aluminium polycrystals; the reasons of grain boundary failure aregrain boundary pores incipient in general type grain boundary. Superplas-tic deformation of Pb-62%Sn alloy goes with decomposition of supersaturated solid solution and structural transformation of a globular eutectic into lamellar (plate-like) one. There was revealed a hydrodynamic mode of deformation under subject to su-perplasticity. The results of the research were included into the lecture courses and practical work. The anticipated estimates of the development of the research object is further studying of the mechanisms of influence of accommodation-relaxation processes for the mechanical properties of polycrystals. Product Description popup.authors popup.nrat_date 2020-04-02 Close