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Information × Registration Number 0222U002753, 0121U111822 , R & D reports Title Technology of combined laser and pulse-plasma application of wear-resistant coatings to strengthen the barrels of firearms. popup.stage_title Head Smyrnov Ihor V., Доктор технічних наук Registration Date 15-02-2022 Organization National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute" popup.description2 A study of the process of laser heating of the surfaces of samples from the material of the machine gun barrel to temperatures <Tpl. The processing conditions are determined, under which highly dispersed microstructures with increased density of dislocations branched in space are formed in materials from various alloys, including model alloys, under laser irradiation. The temperature of each point of the sample for any point in time was determined using the finite difference method. The analysis of types of electron-beam switching elements that have pentode characteristics and withstand longer-term overloads compared to semiconductors, which will provide protection against emergencies (arc, short circuit, etc.) during the development of pulsed ion-plasma nitriding technology. The power supply of pulse excitation of the category with the pulse modulator which is created under certain technological tasks which are defined by the technical task is developed. A pulse modulator has been developed for operation with gas-discharge load in experimental conditions, when arcs and short circuits may occur. An experimental model was created to perform research on the conditions for creating a stable and homogeneous plasma discharge in long tubes of small diameter. The main mode characteristics of ionic nitriding for flat samples are established: glow discharge current 0.6-0.8A, voltage 500-550V, pulse duty cycle 1.5-2, optimal pressure in vacuum chamber 250-500Pa, rational time of nitriding process 5- 6 hours. Flat samples are made of 40X2MA steel with plasma-sprayed coating of HTN-23 powder and additional laser irradiation in different modes to improve the physical and mechanical characteristics of the coatings. Studies of microhardness and wear resistance showed an increase in wear resistance of nitrided surface by 4-5 times, surface hardness by more than 3 times. Product Description popup.authors Bloshchytsyn Mykhailo S. Golovko Leonid F. Kaglyak Oleksiy D. Kuzmichev Anatoly I. Lysak Volodymyr V. Maikut Serhii O. Romanenko Victor V. Smirnov Igor V. Tzybulsky Leonid Yu. Chornyi Andrii V. popup.nrat_date 2022-03-09 Close