Regularities of Formation of the Structure of Composite Antifriction Bronze

Рассмотрены особенности кристаллизации композитных бронз, армированных стальными дендритами, при этом показано влияние никеля на растворимость железа в меди. В структуре дендрита, который по химическому составу представляет собой сталь разных классов, формируются дисперсные выделения в форме пластин матричного состава. Такая структура обеспечивает высокую износостойкость этих бронз, особенно армированных дендритами из аустенитной нержавеющей стали.The features of crystallization of composite bronzes reinforced with steel dendrites are considered, and the effect of nickel on the solubility of iron in copper is shown. In the structure of the dendrite, which by its chemical composition is steel of different classes, dispersed precipitates are formed in the form of plates of matrix composition. This structure provides high wear resistance of these bronzes, especially those reinforced with dendrites of austenitic stainless steel

Tribological Properties of Composite Bronzes Reinforced with Dendrites from Steels of Different Classes

Определены трибологические свойства композитных бронз БрЖНА 12-7-1 и БрЖНХК 12-7-5-1 полученных отливкой, вакуумным литьем и переплавом. Показано, что диспергирование структуры композитных антифрикционных бронз высокой скоростью кристаллизации практически не влияет на коэффициент трения, однако в 5–10 раз снижает интенсивность изнашивания по сравнению с интенсивностью изнашивания отливки.The tribological properties of composite bronzes BrFNA 12-7-1 and BrFNHK 12-7-5-1 obtained by casting, vacuum casting and remelting have been determined. It is shown that the dispersion of the structure of composite antifriction bronzes by a high crystallization rate has practically no effect on the friction coefficient, however, it reduces the wear rate by 5–10 times compared to the wear rate of the castin

Creation of composite bronze-maraging steel alloy

The possibility is demonstrated of creating alloys based on the system Cu-Fe-Ni-Al, within which the matrix is bronze BrNA 4-1, "reinforced" with dendrites containing, apart from Fe and Cu, about 15% Ni and 1% Al. This dendrite composition provides dispersion hardening. Favorable dendrite morphology provides high deformability of these bronzes, and makes it possible to control mechanical and service properties by heat treatment over a wide range. © 2013 Springer Science+Business Media New York

The heating rate influence on the elastic modulus temperature dependence of a corrosion-resistant nickel alloy

The temperature dependence of the elastic modulus of nickel-chromium-molybdenum alloy C4 was investigated by the method of dynamic mechanical analysis. At all heating rates, an abnormal increase in the elastic modulus is observed upon heating in the temperature range of 200-300 °C. It is shown that an increase in the heating rate shifts the beginning of the observed effect to the region of higher temperatures. The temperature anomaly in the elastic modulus of the C4 alloy is explained from the standpoint of the formation of a short-range order in a solid solution. The thermodynamically equilibrium temperature of the "disorder - short-range order" transition in C4 alloy is determined to be 205 °C. © Published under licence by IOP Publishing Ltd

Comparison of the detection of gastrointestinal tract polyps between endoscopists and a neural network trained using artificial intelligence

The purpose of the study is to test and compare the accuracy of determining gastrointestinal polyps between an endoscopist and an AI trained for this task.Цель исследования - сравнить точность определения полипов ЖКТ врачом-эндоскопистом и обученным для этой задачи ИИ

CHOICE OF THE OPTIMAL COMPOSITION OF SAMPLES BASED ON LITHIUM-BORATE FLUXES FOR XRF ANALYSIS OF RED MUD

Sample preparation for XRF analysis of red mud was investigated. Samples were based on lithium-borax fluxes; the effect of flux composition and sample-to-flux ratio on the disk quality was studied. The optimal flux composition is a 1:1 mixture of LiB02 and Li2B40 7, and the optimal ratio of the flux to the sample is 1:2 or 1:4.Работа выполнена при финансовой поддержке Минобрнауки России рамках соглашения о предоставлении субсидии от 29.09.2014 г. № 14.581.21.0002 в рамках ФЦП «Исследования и разработки по приоритетным направлениям развития научно-технологического комплекса России на 2014-2020 годы»

RESEARCH OF KINETICS OF GROWTH IN THE HARDENING PHASES OF LOW-CARBON STEEL BY COMPUTER MODELING

Computer simulation methods using the Thermo — Calc software package have investigated the growth of hardening phases.Методами компьютерного моделирования с использованием программного комплекса Thermo — Calc проведено исследование роста упрочняющих фаз

Choice of Tool Material for Frictional Surface Hardening of Structural Steels

Обоснована возможность применения твердого сплава WC–Co (10 %) с хромом Cr (0,4 %) в качестве ингибитора роста зерен при фрикционной поверхностной закалке углеродистых и легированных сталей. Получены зависимости температуропроводности и теплопроводности материала инструмента в диапазоне температур 25…1050 °C.The possibility of using the hard alloy WC–Co (10 %) with chromium Cr (0.4 %) as a grain growth inhibitor in frictional surface hardening of carbon and alloy steels is substantiated. Dependences of thermal diffusivity and thermal conductivity of the tool material are obtained in the temperature range of 25…1050 °C