Igor Kravchenko

• Doctor of Engineering
• Professor at Russian State Agrarian University - Moscow Timiryazev Agricultural Academy

В статье приводится анализ результатов по исследованию перспективного способа получения функционально-градиентных композиционных материалов на основе применения технологии «холодного» газодинамического напыления. В частности, для композита Al–Al2O3определено влияние содержания керамического компонента на изменение коэффициента термического линейног...

The review, based on the publications by both Russian and international researchers, presents an analysis of the problems of existing technologies for smelting copper concentrates. Three main problems requiring solutions were identified and considered: increasing the efficiency of smelting copper sulfide-containing ores by reducing the copper conte...

Calculations of the residual silicon content in the structure of reaction-sintered silicon carbide are presented. The dependence of the ultimate bending strength on the initial carbon content was experimentally established. The optimal amount of a mixture of powders is determined, which allows obtaining a material with maximum strength. Ill. 5. Ref...

Приведены результаты исследований усталостной прочности конструкционных материалов стали Ст45 и высокопрочного чугуна ВЧ60-2 с плазменными покрытиями относительно большой толщины из порошковой композиции, представляющей собой жаропрочный сплав ЭП-109 (ХН56ВМКЮ) на никелевой основе и алюминиево-магниевый порошок Al–Mg. На основании проведенных экспе...

В статье представлены теоретические расчеты содержания остаточного кремния в структуре реакционно-спеченного карбида кремния. Экспериментально установлена зависимость предела прочности на изгиб от исходного содержания углерода. Определены рациональный фракционный состав и количество углеродной составляющей для получения карбидокремниевой керамики м...

New dependencies and relationships were identified for the first time after the implementation of abrasion-resistant surfacing technology on heat-strengthened steel 65G. This technology revealed the nature of the Vickers hardness distribution in the vertical and horizontal directions of the surfacing area and demonstrated their identity. It has bee...

Представлен современный подход к системам персонализированных рекомендаций, сочетающий в себе графовые нейронные сети GNN с методами обучения с подкреплением RL. GNN-модель оптимизирована для рекомендательных систем и обучается на основе векторных представлений пользователей и продуктов, которые используются для генерации первоначального списка рек...

Gas-thermal spraying of metals and alloys makes it possible to obtain coatings with high performance properties on the surfaces of parts. These coating methods can be effectively used in the restoration of worn-out parts of machines and equipment of various types, which, in the face of large-scale sanctions, is one of the most important tasks of te...

A technological process for hot forging of two-layer forgings with deep cavities and an inverted cone has been developed. A hot forging process flow chart has been analyzed. Digital simulation using QForm software was employed to study the effect of the process parameters on the force characteristics of the metal-forming process, stress-strain cond...

Разработан технологический процесс горячей штамповки двуслойных поковок с глубокими полостями и обратным конусом. Рассмотрена схема технологического процесса горячей штамповки. Цифровым моделированием в программе QForm исследовано влияние технологических параметров на силовые параметры процесса формообразования, напряженно-деформированное состояние...

Впервые получены новые зависимости и взаимосвязи при реализации технологии абразивостойкой наплавки на термоупрочненную сталь 65Г. Выявлен характер распределения твердости по Виккерсу в вертикальном и горизонтальном направлениях области наплавки и показана их идентичность. Установлено, что термические воздействия от сварочной дуги снижают твердость...

Представлены результаты анализа износа ножей измельчителя зерноуборочного комбайна. Установлено, что предельный износ ножей составляет 225 га убранной площади, после чего они подлежат замене. Произведена оценка эффективности методов упрочнения ножей. Используя изменение твердости и микротвердости металлографического и рентгенофазного анализа, опред...

A significant number of different types of structural damages to structural materials, as well as all kinds of scenarios for their accumulation up to destruction, require not only the use of a significant arsenal of experimental methods of theoretical materials science and molecular physics, but also the development of corresponding mathematical mo...

Parts of technological machines, complexes and equipment used in many industries are subject to various types of mechanical wear, which leads to a significant decrease in their durability and an increase in maintenance and operating costs. Promising directions for improving the technologies of plasma application of wear-resistant coatings have been...

The paper is devoted to studying the structure and microhardness of protective oxide-ceramic coatings obtained by micro-arc oxidation on the deposited surfaces of parts. Experimental researches were carried out with the use of the commonly used perfected methods and up-to-date measuring instruments and equipment. AlSi7Mg aluminum alloy was used to...

The improvement of the technology of plasma deposition of wear-resistant coatings is shown. At the same time, special attention is paid to one of the most important parameters ― the thickness of the functional layer, since when using plasma deposition methods, it has a significant impact on the quality of coatings, as well as the functionality and...

Our country has been undergoing processes related to the reorganization and improvement of agricultural production services. The Soyuzselkhotechnika system was organized to replace the machine-technological stations. The development dynamics of Soyuzselkhotekhnika shows the volumes of marketable products, and it is particularly noted that the marku...

This article deals with methodological support for the design of effective supersonic flat external compression input devices. A concise analysis of the contribution of well-known scientists in the study of braking processes of supersonic flows of the working body in the system of sealing jumps is presented in the input devices. The proposed method...

A review and analysis of the influence of electrospark treatment on the residual fatigue limit of parts as well as of the degree of influence of electrospark surfacing on the fatigue strength of automotive parts restored by electrospark treatment are given. We present rational technological regimes for electrospark coating deposition and rolling un...

In conditions of growing loads and temperatures on engineering products, the problem of choosing efficient materials is relevant, especially in the realities of import substitution. One of such tasks for modern materials science is the production of high-temperature products of special engineering, including complex shapes. Metal and ceramic materi...

Статья посвящена оценке эффективности новой технологии ремонта шестеренных насосов с восстановлением изношенных поверхностей ресурсоопределяющих сопряжений деталей и повышением их износостойкости. Отремонтированные по предложенной технологии гидронасосы показали увеличение среднего межремонтного ресурса в условиях реальной эксплуатации в 1.07 раза...

The efficiency of an aircraft engine is estimated by many parameters, one of which is the thrust force. Improving the efficiency of aircraft engines is an important task for engine building. However, questions remain regarding the effect of the number of blades on the change in the thrust of the ducted and unducted fans. In this work, the object of...

У статті розглядається організація тренувального процесу футзалістів, охарактеризовані завдання та методи тренувального заняття. Мета роботи – дослідити та впровадити у тренувальний процес методику покращення фізичних якостей студентів-футзалістів, які займаються у групі підвищення спортивної майстерності «Футзал» закладу вищої освіти. Методологія...

The article considers the main prospects for the use of the method of coating plasma spraying. The essence of plasma spraying is disclosed, and the main advantages and disadvantages of this coating formation method are indicated. The method is characterized by high productivity and the possibility of forming high-quality coatings on machine parts f...

Based on experiments, wear increase directly proportional to the test duration is shown, and the wear intensity has two phases, adaptation to the abrasive environment and subsequent stabilization. Increasing the rotation speed of the holder with the samples over 800–1000 min–1 does not affect the decrease in the testing duration. We show that the i...

The main defect that occurs when using plows is an abrasive wear of its ploughshares, the greatest wear of which is observed in the nose. When renestoring worn plowshares in order to significantly increase their service life, it is advisable to use technical ceramics. A plowshare with soldered ceramic-metal plates was chosen as the investigation ob...

Problems of the kinetic theory of strength and the influence of temperature and force factors on the accumulation of irreversible damage in materials are considered.