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Information × Registration Number 0305U003269, 0103U004187 , R & D reports Title Influence of structural changes and external factors on mechanical and relaxation properties of materials popup.stage_title Вплив зовнішніх чинників на механічні та релаксаційні властивості матеріалів Head Andronov V.M., Registration Date 04-03-2005 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of the experimental studies are filament crystals of copper with ad-mixture of tin and silver; the alloys Fe-(9,4-40,0) at.%Al, Fe-34,9 at. % Ni; the alloy 1460 based on Al (mas.%): Al-2,64% Cu-2,2% Li-0,12% Zr-0,12% Sc. The aim of the second stage of the work is a study of the influence of external factor on relaxation characteristics of ordering alloys on the base of iron and particu-larities of their structured condition, structure features and their evolutions in the sam-ple of 1460 alloy superplastically deformed at high gomologous temperatures, change of parameters of plastic flow of filament crystals due to temperature-speed condition of deformation. Methods of investigations are structural and mechanical tests, mechanical spectroscopy, X-Ray analysis, fractography and thermal gravimetry. The studies of the influence of silver admixtures on mechanical characteristic of filament crystals of copper indicate on general nature of obtained deformation effects: change of stages of deformation diagram, reduction on order of the value of amplitude of stress jumps, reduction of general deformation up to destruction, increasing of de-forming stresses and factor of strenthening, presence of critical concentration of ad-mixtures, under which occur specified change. Change of temperature-speed condi-tions points to athermal character of the dislocation motion in up-to-critical range, and thermally activated in overcritical range of concentration. It is established that one of the effective methodes of the analysis of nonequilib-rium ordering systems by the method of mechanical spectroscopy is studying an аm-plitude dependencies of damping at different temperatures. A hysteresis effects inves-tigations in magnetic field in ordered alloys of the Fe-Al system have shown that at Т " 450 К approaching at Al contents more than 21,7 at. % amplitude dependencies be-came nonmonotonic with significant hysteresis, which is linked with the change of the ordered condition. The deformation of 1460 alloy samplesuperplastic deformed up to destruction is realized predominantly due to inter-grain-boundary slippage. At heating up to tem-peratures, under which alloy became superplasticity (Т " 823 К), as a result of phase transition can be formed fluid phase due to partial melting of the alloy, about which witness fibrous-like formations, which are localized in under surface pores and rifts. The samples destruction, which were deformed superplastically in all explored interval of the temperature, on macro-level is quasi-brittle. The SIW results can serve the base for revision of the ideas about plasticity and superplasticity to work out a new composite materials. Product Description popup.authors popup.nrat_date 2020-04-02 Close