Search academic texts

Information × Registration Number 0308U001432, 0106U005492 , R & D reports Title Microplastic, macroplastic and superplastic deformation interconnection in the context of structural state of materials popup.stage_title Термоактиваційні параметри пластичної деформації металевих матеріалів Head Andronov Volodimir Mihailovich, Registration Date 04-02-2008 Organization Kharkov national university named after V.N. Karazin popup.description2 Objects of experimental researches - deformable industrial aluminum alloys: 1420, 6111, AK 4-1 AMg6, model aluminum alloy: Al-5wt.%Mg, amorphous metallic alloy Ni78Si8B14. The purpose of the second stage of work is an elucidation of essence of physical processes, which occur in specimens of aluminum alloys 1420, AMg6, AK4-1, 6111 during their heating to high homologous temperatures, above which they display the effect of high-temperature structural superplasticity being deformed in creep regime under constant flow stress. The aim is also an establishment of the most probable reasons of partial melting of the specimens of investigated alloys during their heating, the obtaining data about structural state of AMg6 alloy's specimens, which displayed the structural superplasticity in solid-liquid state, an establishment of the mechanism of their superplastic deformation and its accommodation, the determination of the effective activation energy of superplastic flow of this alloy. The purpose also concludesin the investigation of the temperature influence on frequency dependences of parameters of the elastic energy and the relaxation of stresses in amorphous metallic alloy Ni78Si8B14 and the determination of thermoactivation parameters of its plastic deformation. Methods of research - mechanical tests, mechanical spectroscopy, metallography, raster electronic microscopy, the thermal analysis. The probable reasons of the partial melting of number of aluminum-based matrix alloys, which occurs in them during the heating to high homologous temperatures above which they display the effect of high-temperature structural superplasticity, are determined. The peculiarities of the structural state of superplastically deformed in solid-liquid state aluminum-based AMg6 specimens are defined and the effective activation energy of its superplastic deformation mechanism is determined. The mechanical spectrum (frequency dependences of the elastic energy dissipation) and the relaxation of the axial stresses in the specimens ofamorphous metallic alloy Ni78Si8B14 under the test temperature variation are investigated. A number of thermoactivation parameters of the plastic deformation (structural relaxation) mechanism are determined. The results of SRW may be used for improvement of physical theories and specification of representations about microplasticity, plasticity, superplasticity and internal friction of crystal and amorphous materials, and also by development new constructional and, in particular, composite materials. Product Description popup.authors popup.nrat_date 2020-04-02 Close