This article describes the design and development of a multi-megawatt radar "Ruza," having a large mechanically steered, millimeter-wave, , phased-array antenna.

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Abstract--This paper discusses the use of some relatively new quasi-optical structures for configuring high-power gyrotronbased millimeter-wave systems for plasma fusion, microwave technologies, electron accelerators, radar and communication. Techniques for wave combining and switching, and for wave matching to transmitters, receivers and antennas are analyzed.

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Relevance. Tractors are distinguished by long inter-service ranges and easy maintenance. But if the tractor components are not serviced in a timely manner (oil change, filters, and so on), the resulting contamination will begin to damage the parts, and increased friction will contribute to their wear and overheating. Since there is currently an acute shortage of original spare parts and their prices are quite high, the development of technological solutions for the restoration of worn-out seats of tractor parts is relevant. One of the coating methods, namely electric arc spraying, can solve this problem.   The purpose of the study: using the example of the drive axis of a cylindrical straight tooth gear of a “John Deere” tractor, develop a technology for restoring a worn-out seat by electric arc spraying for the installation of a bearing or an oil seal.   Methods. The brand of the axis material corresponding to the Russian analogue has been determined. The hardness of the axis base was measured with a TK-2M hardness tester. Preliminary mechanical treatment of the restored surface has been carried out. Additionally, jet-corundum treatment of the worn surface was carried out. The technology of electric arc spraying has been applied to obtain the necessary coating. Turning of the restored surface was performed until the nominal diameter of the axle seat was obtained.   Results. The technology of restoration of the axle seat by supersonic electric arc spraying has been developed. The expediency and necessity of preliminary mechanical action on the seat, consisting in threading and jet-corundum processing, before the process of supersonic electric arc spraying are established. The results of the study showed the effectiveness of the electric arc spraying method for restoring the worn-out seat of the drive axis of a cylindrical straight tooth gear in tractors. The cost of restoring one worn-out axle seat was 3,000 rubles, which is more than 10 times cheaper than the original spare part. At the same time, all the mechanical properties of the part have been preserved. It is recommended to use the method of electric arc spraying to restore the worn-out seat of the axles of all imported agricultural machines.

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The application of various types of functional and protective coatings made of inorganic materials to parts made of conventional structural materials will be able to solve the issue of ensuring the planned service life of modern devices, machines and mechanisms. Electric arc metallization, characterized by relatively high productivity and low cost of coating, serves as one of the methods of applying gas-thermal coatings. However, the high porosity of the resulting coatings, their low adhesion strength to the substrate and plastic properties prevent the widespread use of this method. (Research purpose) The research purpose is in studying the chemical, thermal and mechanical effects on samples obtained by electric arc metallization, on the adhesive, cohesive and strength properties of the coating and the areas of connection of the coating with the substrate. (Materials and methods) The authors used electric arc metallization and gas-dynamic spraying to obtain the necessary coatings. A mechanical effect on the coating was studied using the machine IZH- 250TV and special research equipment to determine the properties of coatings and substrates. (Results and discussion) Gas-thermal coatings can be successfully used in the manufacture of new and restoration of worn parts of agricultural machinery. The processing of metallized samples by surface plastic deformation are expedient and necessary. Chemical and thermal treatment has a positive effect on the properties of the coating and the substrate, increasing the value of microhardness by 50-70 percent. The use of supersonic metallization devices leads to an increase in adhesive strength by 30-35 percent. (Conclusions) The study showed that chemical and thermal treatment has a positive effect on the properties of the coating. Plastic deformation of the sprayed surfaces is practically equivalent to thermodynamic effect. It is recommended to use plastic deformation for spraying cylindrical surfaces.