СТРУКТУРА И МЕХАНИЧЕСКИЕ СВОЙСТВА СЛИТКОВ И ПРОФИЛЕЙ ИЗ АЛЮМИНИЕВОГО СПЛАВА НА ОСНОВЕ СИСТЕМЫ AL-MG-MN

Commercial ingots and hot-pressed rolled sections of Al-Mg-Mn alloy doped with zinc, scandium, zirconium, chromium, and vanadium have been studied using optical microscopy, thermal analysis, electron microscopy, and electron-probe microanalysis. The compositions of the phase constituents and aluminum matrix of the alloy are determined. The sensitivity of the alloy to the formation of complex intermetallic compounds during solidification is revealed. The mechanical properties of ingots and rolled sections are determined. © 2013 Pleiades Publishing, Ltd

Evidence for spin-triplet superconducting correlations in metal-oxide heterostructures with non-collinear magnetization

Heterostructures composed of ferromagnetic La0.7Sr0.3MnO3, ferromagnetic SrRuO3, and superconducting YBa2Cu3Ox were studied experimentally. Structures of composition Au/La0.7Sr0.3MnO3/SrRuO3/YBa2Cu3Ox were prepared by pulsed laser deposition, and their high quality was confirmed by X-ray diffraction and reflectometry. A non-collinear magnetic state of the heterostructures was revealed by means of SQUID magnetometry and polarized neutron reflectometry. We have further observed superconducting currents in mesa-structures fabricated by deposition of a second superconducting Nb layer on top of the heterostructure, followed by patterning with photolithography and ion-beam etching. Josephson effects observed in these mesa-structures can be explained by the penetration of a triplet component of the superconducting order parameter into the magnetic layers.Comment: 10 pages, 6 figure

Parameters of Load-Displacement Curves and Their Correlation with the Fracture Surface in Medium-Carbon Steel

Impact tests are mandatory for a wide range of structural steel products to evaluate the required service life and operational safety. This test is especially relevant for products used in operation in climatic areas with a cold climate, since it allows one to determine the temperature range of the ductile-brittle transition. Depending on the structural-phase state of a metal, the type of the temperature relationship of impact toughness and its displacement on the temperature axis may differ significantly. For ductile materials, the temperature range of the ductile-brittle transition is shifted towards ultra-low negative temperatures whereas for materials in the embrittled condition it lies in the region of higher temperatures. Ductile-brittle transition behavior of medium-carbon steel with 0.32% C-1.35% Mn-0.003% B in two conditions (after normalization and after quenching and tempering) by instrumented impact testing and fracture analysis was studied. On the descending branch of the force-displacement curves the periods corresponding to different zones of propagation of the main crack are distinguished: period I is the ductile zone of pure shear, period II is the zone of brittle fracture, period III is the ductile zone of break fracture. Each period can be quantitatively described by a set of strength, plastic and gradient parameters. It is established that the displacement to the beginning of linear period II (SIIb ) and slope of the curve on it (ΔF/ΔS)II have a better correlation with shear fracture zone percentage (B) than the other distinguished parameters of force-displacement curves. © 2021, Institute for Metals Superplasticity Problems of Russian Academy of Sciences. All rights reserved

Lie group analysis for multi-scale plasma dynamics

An application of approximate transformation groups to study dynamics of a system with distinct time scales is discussed. The utilization of the Krylov-Bogoliubov-Mitropolsky method of averaging to find solutions of the Lie equations is considered. Physical illustrations from the plasma kinetic theory demonstrate the potentialities of the suggested approach. Several examples of invariant solutions for the system of the Vlasov-Maxwell equations for the two-component (electron-ion) plasma are presented.Comment: Latex, 15 pages, 7 figure. This is an enlarged contribution to Journal of Nonlinear Mathematical Physics v.18, Suppl. 1 (2011) p.163-175 with modest stylistic corrections introduced mainly in the third Sectio

OPTIMIZATION OF HEAT TREATMENT OF DEFORMABLE ALUMINUM ALLOY 1200

В работе представлены результаты исследования влияния режимов термической и деформационной обработок слитков алюминиевого сплава 1200 системы Al-Cu-Mn на механические свойства экструдированных полуфабрикатов. Продемонстрирована возможность при сохранении требуемого высокого уровня прочностных характеристик в состоянии полной термической обработки (ТО) прутков снизить температуру и сократить время гомогенизирующей ТО слитков с 530 °С и 12 часов, до 420 °С и 2 часов, с одновременным понижением температуры прессования с 480 до 330 °С.The paper presents the results of the study of the influence of the heat and deformation treatment of aluminum alloy 1200 ingots (Al-Cu-Mn system) on the mechanical properties of extruded semi-finished products. For the pressed rods the possibility to decrease the temperature and reduce the time of homogenizing of ingots from 530 °С 12 hours to 420 °С 2 hours, and simultaneously to reduce of the pressing temperature from 480 to 330 °С was demonstrated

Features of Influence of Heat- and Deformation Treatments on Mechanical Properties of Al–Cu–Mn–Ti

The influence of heat- and deformation treatments on the microstructure and mechanical properties of Al–Cu–Mn–Ti alloy was investigated. It was demonstrated that in case of time reduction of cast ingots heat treatment with simultaneous reduction of deformation temperature, it is possible to provide an increased level of rod strength characteristics.Исследовано влияние термической и деформационной обработок на микроструктуру и механические свойства сплава Al–Cu–Mn–Ti. Продемонстрирована возможность при сокращении времени термической обработки (ТО) литых слитков с одновременным понижением температуры деформации прессованием обеспечить повышенный уровень прочностных характеристик прутков в состоянии полной ТО

The Effect of Heat Treatment on the Mechanical Properties Level of Low-Carbon Chromium Steels

Объектом исследования являлись образцы конструкционных низкоуглеродистых хромистых сталей. Изучено влияние легирования и параметров отпуска на комплекс механических свойств. Методами макроанализа и растровой электронной микроскопии изучены поверхности разрушения образцов после испытаний на ударный изгиб.The object of the study were samples of low-carbon chromium steels. The influence of alloying and tempering parameters on the complex of mechanical properties was studied. The fracture surfaces of samples after impact tests investigated by means of macro analysis and scanning electron microscopy