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Information × Registration Number 0224U032623, (0123U103486) , R & D reports Title The concept of restoring and extending exploitation resource of equipments of the most important branches of the national economy of Ukraine popup.stage_title Встановлення закономірностей формування структури електродугових покриттів, визначення їх фізико-механічних характеристик при напиленні за стандартного (0,6 МПа) та підвищеного тиску (1,0...1,2 МПа) розпилюючого струменю. Дослідження зносостійкості та трибологічних характеристик отриманих покриттів. Дослідно-промислова перевірка напилених покриттів на деталях сільськогосподарської та харчопереробної галузі. Підготовка технологічного регламента відновлення деталей типу "вал" методом електродугового напилення покриттів із порошкових дротів системи легування Fe-Cr-Si-Mn-C для потреб сільськогосподарської, харчопереробної, комунальної, транспортної та оборонної галузі. Head Student Mykhailo M., Доктор технічних наук Registration Date 27-11-2024 Organization Physico-Mechanical Institute named after GV Karpenko of the National Academy of Sciences of Ukraine popup.description1 The goal of the project development of wear resistant electric arc spray coatings from powder-cored wires of Fe-Cr-SiMn-B-C alloying system to increase the resource of new and restore the performance of worn parts of the «shaft» type exploited under the high specific loads, boundary lubrication and presence of abrasive, and organization of a research and production center «Laboratory of methods of gas thermal spraying of coatings» for the restoration of the parts of the most important branches of Ukraine's economy. popup.description2  For the first time, CW alloying systems Fe-Cr-Si-Mn-Ti-B-C with an exothermic charge Cr(Fe)+B4C have been developed, facilitating exothermic reactions between the charge components. As a result, additional thermal energy is released during coating spraying, and superhard nanosized particles of (FeCr)2B borides are formed in the coating structure, which improves the physical and mechanical properties of the coating as a whole. To reduce the melting point of refractory oxides (Сr2O3 – 2435оС, Al2O3 – 2050 оС, SiO2 – 1700оС, Fe2O3 – 1566оС) on the surface of CW melt droplets, up to 1 wt.% Na2B4O7 or B2O3 was added to their charge. A design of a nozzle system of a metallizer for the implementation of supersonic spraying of coatings at increased air pressure (from the generally accepted 0.6 to 1.2 MPa) was developed. This design uses a double Laval nozzle, providing a change in the droplet velocity in the metal-air flow from 130 to 250 m/s. It was established that the wear resistance of the coatings increases with an increase in the chromium and boron content in the CW charge, related to the Fe-Cr-Si-Mn-B-C alloying system. Moreover, this was achieved using both subsonic and supersonic modes of spraying coatings. The maximum positive effect of the supersonic coating spraying mode was twice as high as the wear resistance of U12 steel with a hardness of 840 HV0.3. The addition of borax (Na2B4O7) or boric anhydride (B2O3) to the charge of CW 90Cr6BMnSi was accompanied by an increase in the wear resistance of the coatings by 25 and 35%, respectively. At the same time, the tribological characteristics of the coatings were equal to or exceeded the tribological characteristics of both quenchened steel 45 and the coating with galvanically applied chromium. Product Description popup.authors Hvozdetskyi Volodymyr M. Zadorozhna Khrystyna R. Kovalchuk Ihor V. Lavrys Serhii M. Lukianenko Oleksandr Н. Pohreliuk Iryna M. Student Mykhailo M. Student Oleksandra Z. Tkachuk Oleh V. Chornenkyi Andrii В. popup.nrat_date 2024-11-27 Close