Получение композиционного керамического материала для газотермического напыления Канд. техн. наук В. А. Оковитый 1) , чл.-кор. НАН Беларуси, докт. техн. наук, проф. Ф. И. Пантелеенко 1) , асп. В. В. Оковитый 1) , чл.-кор. НАН Беларуси, докт. физ.-мат. наук, проф. В. М. Асташинский 2) 1) Белорусский национальный технический университет (Минск, Республика Беларусь), 2) Институт тепло-и массообмена имени А. В. Лыкова НАН Беларуси (Минск, Республика Беларусь)

The article presents experimental studies of composite powder materials for plasma spraying, obtained by the method of diffusion doping of powder materials based on austenitic steels. It is indicated that the main factors forming the diffusion layer on a powder material are a composition of the required saturating medium, treatment temperature and duration of chemical and thermal exposure. Creation of single-phase diffusion layers is possible only in the case of a minimum level of temperature-time characteristics during heat treatment. This is also facilitated by the use of media with a low concentration of boron and introduction of additives inhibiting saturation process (such as carbon, aluminum, silicon) into a saturating mixture of powder. Structure and composition of powders have been thoroughly investigated with the help of X-ray microanalysis that has made it possible to study location of elements contributing to powder alloying and micro-durametric characteristics. A component of high-boride phase is increasing due to higher degree of powder material alloying. Significant changes in phase composition, as well as the chemical one, are noticeable in diffusion processing of the following alloyed powder materials: РR-Х18N9, РR-Х18N10, РR-Х18N15. Free carbon being displaced by boride into a transition zone creates dispersed complex carbide compounds with chromium. This is confirmed by distribution nature of carbide-forming components in a powder particle. All carbide-forming elements have characteristic concentration peaks-bursts in contrast to non-carbideforming silicon. Silicon is practically not present in the considered FeB phase and it is found only in a very small amount in the studied Fe2B phase; it is pushed aside by high-boride phases to a sublayer. The change in microhardness of the FeB and Fe2B phases under study is associated with dissolution of corresponding alloying elements in them and distortions of a crystal lattice in borides. A similar phenomenon is also characteristic for saturation while using boron or while making chemical and thermal treatment of alloyed steels, it has been noted in a number of studies. The increase in microhardness of a particle nucleus during its boriding is caused by displacement of carbon and alloying elements by growing front of boride phases. A core zone moves with an increased microhardness to a particle core while increasing temperature mode and time of boronization and up to realization of the effect with counter diffusion.

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The paper presents studies on the optimization of the process of applying coatings from cermet powders with different solid phase contents by plasma spraying in air to restore and harden parts of machines and mechanisms operating under adverse conditions. Such conditions are usually created in heavily loaded tribojoints when the mechanisms operate at a low speed of relative movement of surfaces during friction. At the same time, the destruction of the working surfaces is mainly due to the process of microcontact setting and subsequent detachment of the formed particles at their contact points. The application of special protective coatings with the required properties is possible with the manufacture of high-quality starting powder materials and optimization of the technology for their application. Such powders and powder compositions can be obtained by the method of agglomeration of a fine powder mixture with its subsequent high-temperature sintering. To identify the hardening mechanism of composite coatings made of cermet by gas-thermal spraying, important stages are the optimization of the deposition process parameters and the study of the properties of plasma coatings obtained in this case. When optimizing the technological parameters of plasma spraying of coatings, the utilization rate of the sprayed powder material has been taken into account as the main indicator of the process efficiency, the structure of the obtained layers, and the morphology of individual particles deposited on the polished surface. The paper provides data on the structural elements of sprayed materials for wear-resistant coatings obtained by plasma spraying at optimal conditions. Taking into account the processes that occur during the wear of tribological conjugations, the data indicate the existing prerequisites for the wear resistance of the studied composite coatings made of metal ceramics. Special wear-resistant coatings made of materials with a soft matrix hardened by solid inclusions Al2O3–TiO2–Ni–Cr–Al–Y are widely used in various industries. Based on the detailed analysis of the features of cermet plasma coatings, it can be stated that such powder compositions (complex oxides-metal component) are often used as wear-resistant plasma coatings. The research results can be taken into account in cases of application of wear-resistant plasma coatings made of metal-ceramics and compositions based on them, containing solid phases in the form of oxides, as well as the manufacture of a whole range of parts operating under conditions of intense wear.

Формирование и исследование многослойных композиционных плазменных оксидных покрытий на элементах экранной противометеорной защиты Канд. техн. наук В. А. Оковитый 1) , докт. техн. наук, проф., чл.-кор. НАН Беларуси Ф. И. Пантелеенко 1) , докт. техн. наук, проф. О. Г. Девойно 1) , асп. В. В. Оковитый 1) , докт. физ.-мат. наук, проф., чл.-кор. НАН Беларуси В. М. Асташинский 2) , докт. физ.-мат. наук П. П. Храмцов 2) , канд. физ.-мат. наук М. Ю. Черник 2) , докт. физ.-мат. наук, проф. В. В. Углов 3) , канд. техн. наук С. Б. Соболевский 4) 1) Белорусский национальный технический университет (Минск, Республика Беларусь), 2) Институт тепло-и массообмена имени А. В. Лыкова НАН Беларуси (Минск, Республика Беларусь), 3) Белорусский государственный университет (Минск, Республика Беларусь), 4) РУП «БелНИИТ «Транстехника» (Минск, Республика Беларусь)