DEVELOPMENT OF WEAR RESISTANT COATINGS FORMED BY PLASMA SPRAYING OF ALLOY Ni–Fe–Cr–Si–B–C SYSTEM REINFORCED WITH CERAMICS Al2O3

Abstract

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 Application of Transmission Electron Microscopy to the Analysis of Powder Coatings Deposited on Metal Substrates by Plasma Method

“…This is one of the advantages of the thermal spraying process. Thus, thermal coating spraying finds application in various industries for deposition of wearresistant, a corrosion resistant and heat-resistant, bioceramic, decorative and other types of coatings [1,2]. The main purpose of thermal sprayed coatings is normally protection of surfaces of parts operating under conditions of increased friction, temperatures and aggressive environments: cylinder liners, shafts, etc.…”

Developing a New Resource and Energy Saving Technology of Precision Application of Powder Coating Multifunctional Systems

“…Nowadays, various types of thermal spray coating processes for surface protection against temperature extremes, corrosion, and wear are widely used all over the world [1,2]. Amongst different existing plasma spraying processes, the microplasma spraying (MPS) is particularly characterized by low plasma power, low plasma gas flow rate, small spray spot (1-8 mm).…”

“…Most thermal spray powder coatings require additional processing such as heat treatment by irradiation after deposition of the coating [2]. Typically, additional processing of the powder plasma coatings by irradiation is used to melt the coating in order to reduce its roughness and increase the homogeneity of its structure, as shown in [1,5,6].…”

Evaluation of Wear Resistance of Copper at Sliding against TiC Based Coatings under Load

“…For the production of copper wire, it is possible to use a composite coating based on self-fluxing nickel alloys with neutral oxide ceramics Al 2 O 3 by plasma spraying. [6] In [7], the adhesive interaction of a copper wire and silicon nitride was investigated. A ceramic alloy is proposed as a rolling roll made of silicon nitride powder (Si 3 N 4 , CeramTec AG, Germany).…”