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Abstract. Creating a functionally oriented, including nanostructured, anti-friction materials and coatings with qualitatively new complex of service properties is an important scientific and practical problem. In particular, for the cable industry it is urgent task of ensuring the high performance properties of fast deteriorating stretching and supporting rollers. Working surfaces of these parts operate under practically dry friction conditions with constantly updated material of stretching wire. Plasma spraying is one of the widely used methods of surface engineering to create wear resistant coatings and which is characterized with process flexibility and the ability to create coatings using various materials and alloys including composite ones. The installation UPU-3D with the PP-25 plasma torch was used for plasma spraying. The thickness of the sprayed layer was 0.8-1.1 mm. As a material for the deposition of composite coatings a powder mixture of self-fluxing nickel alloy PG-HN80SR4 (system Ni-Fe-Cr-Si-B-C) and a neutral oxide ceramics Al 2 O 3 was used. The amount of ceramics varied from 15 to 33 %. This ceramic oxide was selected due to the desire to reduce coatings' costs while providing high durability. Carried out phase and microstructural studies have shown when ceramics was added in an amount more than 20 % a formation of conglomerates formed by not melted alumina particles often was observed. These conglomerates serve as crack formation centers in the coating. The phase composition of the coatings practically does not depend on the content of ceramics compounds. Tribological tests have shown that the best results were obtained when the content of the oxide ceramic in the coating was in the range from 15 to 20 %. Реферат. Создание функционально ориентированных, в том числе наноструктурированных, антифрикционных мате-риалов и покрытий, обладающих качественно новым комплексом служебных свойств, является важной научной и практической задачей. В частности, для кабельного производства актуальна задача обеспечения высоких эксплуа-тационных свойств быстроизнашивающихся протягивающих и поддерживающих роликов кабельного производства. Рабочие поверхности этих деталей работают в условиях практически сухого трения при постоянно обновляющемся материале протягиваемой проволоки. Один из широко применяемых методов инженерии поверхности для создания износостойких покрытий -плазменное напыление, которое характеризуется гибкостью процесса и возможностью создавать покрытия из различных материалов и сплавов, включая композиционные покрытия. Для плазменного напыления использовали установку УПУ-3Д с плазмотроном ПП-25. Толщина напыленного слоя составила 0,8-1,1 мм. В качестве материала для создания композиционных покрытий применяли смесь порошков самофлюсующегося нике- и Машиностроение левого сплава ПГ-ХН80СР4 (системы Ni-Fe-Cr-Si-B-C) и нейтральной оксидной керамики Al 2 O 3 . Количество вво-димой керамики изменялось от 15 до 33 %. Выбор данной оксидной керамики обусловлен стремлением снизить сто-имость покрытия при обеспе...

The variety of requirements for friction pairs requires the development of different technologies for the production of tribological materials with reference to the operation modes. Composite materials obtained by the casting technology have been successfully applied for the normalization of the thermomechanical state of the steam turbines. These composites consist of the matrix based on copper alloys reinforced with cast iron granules. Because the structure and properties of cast iron are determined by the conditions of their production studies have been conducted on determination of preparation conditions on grain structure and properties of the synthesized composite material. Using an upgraded unit for production of granules technological regimes were determined providing narrow fractional composition. It has been found that granules formed are characterized with typical microstructure of white cast iron containing perlite and ledeburite. Microhardness of pilot cast iron granules is characterized by high values (from 7450 up to 9450 MPa) and depends on the size of the fraction. Composite materials obtained using experimental granules had a microhardness of the reinforcing cast iron granules about 3500 MPa, and a bronze matrix – 1220 MPa, which is higher than the hardness of the composite material obtained by using the annealed DCL-1granules (2250 MPa). Metal base of experimental granules in the composite material has the structure of perlitic ductile iron with inclusions of ferrite not exceeding 10–15% and set around a flocculent graphite. As a result, the increase of physical-mechanical properties of finished products made of composite material is observed.