Vol. 24 No. 3 2022 3 EDITORIAL COUNCIL EDITORIAL BOARD EDITOR-IN-CHIEF: Anatoliy A. Bataev, D.Sc. (Engineering), Professor, Rector, Novosibirsk State Technical University, Novosibirsk, Russian Federation DEPUTIES EDITOR-IN-CHIEF: Vladimir V. Ivancivsky, D.Sc. (Engineering), Associate Professor, Department of Industrial Machinery Design, Novosibirsk State Technical University, Novosibirsk, Russian Federation Vadim Y. Skeeba, Ph.D. (Engineering), Associate Professor, Department of Industrial Machinery Design, Novosibirsk State Technical University, Novosibirsk, Russian Federation Editor of the English translation: Elena A. Lozhkina, Ph.D. (Engineering), Department of Material Science in Mechanical Engineering, Novosibirsk State Technical University, Novosibirsk, Russian Federation The journal is issued since 1999 Publication frequency – 4 numbers a year Data on the journal are published in «Ulrich's Periodical Directory» Journal “Obrabotka Metallov” (“Metal Working and Material Science”) has been Indexed in Clarivate Analytics Services. We sincerely happy to announce that Journal “Obrabotka Metallov” (“Metal Working and Material Science”), ISSN 1994-6309 / E-ISSN 2541-819X is selected for coverage in Clarivate Analytics (formerly Thomson Reuters) products and services started from July 10, 2017. Beginning with No. 1 (74) 2017, this publication will be indexed and abstracted in: Emerging Sources Citation Index. Journal “Obrabotka Metallov” (“Metal Working & Material Science”) has entered into an electronic licensing relationship with EBSCO Publishing, the world's leading aggregator of full text journals, magazines and eBooks. The full text of JOURNAL can be found in the EBSCOhost™ databases. Novosibirsk State Technical University, Prospekt K. Marksa, 20, Novosibirsk, 630073, Russia Tel.: +7 (383) 346-17-75 http://journals.nstu.ru/obrabotka_metallov E-mail: metal_working@mail.ru; metal_working@corp.nstu.ru
OBRABOTKAMETALLOV Vol. 24 No. 3 2022 4 EDITORIAL COUNCIL EDITORIAL COUNCIL CHAIRMAN: Nikolai V. Pustovoy, D.Sc. (Engineering), Professor, President, Novosibirsk State Technical University, Novosibirsk, Russian Federation MEMBERS: The Federative Republic of Brazil: Alberto Moreira Jorge Junior, Dr.-Ing., Full Professor; Federal University of São Carlos, São Carlos The Federal Republic of Germany: Moniko Greif, Dr.-Ing., Professor, Hochschule RheinMain University of Applied Sciences, Russelsheim Florian Nürnberger, Dr.-Ing., Chief Engineer and Head of the Department “Technology of Materials”, Leibniz Universität Hannover, Garbsen; Thomas Hassel, Dr.-Ing., Head of Underwater Technology Center Hanover, Leibniz Universität Hannover, Garbsen The Spain: Andrey L. Chuvilin, Ph.D. (Physics and Mathematics), Ikerbasque Research Professor, Head of Electron Microscopy Laboratory “CIC nanoGUNE”, San Sebastian The Republic of Belarus: Fyodor I. Panteleenko, D.Sc. (Engineering), Professor, First Vice-Rector, Corresponding Member of National Academy of Sciences of Belarus, Belarusian National Technical University, Minsk The Ukraine: Sergiy V. Kovalevskyy, D.Sc. (Engineering), Professor, Vice Rector for Research and Academic Affairs, Donbass State Engineering Academy, Kramatorsk The Russian Federation: Vladimir G. Atapin, D.Sc. (Engineering), Professor, Novosibirsk State Technical University, Novosibirsk; Victor P. Balkov, Deputy general director, Research and Development Tooling Institute “VNIIINSTRUMENT”, Moscow; Vladimir A. Bataev, D.Sc. (Engineering), Professor, Novosibirsk State Technical University, Novosibirsk; Vladimir G. Burov, D.Sc. (Engineering), Professor, Novosibirsk State Technical University, Novosibirsk; Aleksandr N. Gerasenko, Director, Scientifi c and Production company “Mashservispribor”, Novosibirsk; Sergey V. Kirsanov, D.Sc. (Engineering), Professor, National Research Tomsk Polytechnic University, Tomsk; Aleksandr N. Korotkov, D.Sc. (Engineering), Professor, Kuzbass State Technical University, Kemerovo; Evgeniy A. Kudryashov, D.Sc. (Engineering), Professor, Southwest State University, Kursk; Dmitry V. Lobanov, D.Sc. (Engineering), Associate Professor, I.N. Ulianov Chuvash State University, Cheboksary; Aleksey V. Makarov, D.Sc. (Engineering), Corresponding Member of RAS, Head of division, Head of laboratory (Laboratory of Mechanical Properties) M.N. Miheev Institute of Metal Physics, Russian Academy of Sciences (Ural Branch), Yekaterinburg; Aleksandr G. Ovcharenko, D.Sc. (Engineering), Professor, Biysk Technological Institute, Biysk; Yuriy N. Saraev, D.Sc. (Engineering), Professor, Institute of Strength Physics and Materials Science, Russian Academy of Sciences (Siberian Branch), Tomsk; Alexander S. Yanyushkin, D.Sc. (Engineering), Professor, I.N. Ulianov Chuvash State University, Cheboksary
Vol. 24 No. 3 2022 5 CONTENTS OBRABOTKAMETALLOV TECHNOLOGY Permyakov G.L., Davlyatshin R.P., Belenkiy V.Y., Trushnikov D.N., Varushkin S.V., Pang S. Numerical analysis of the process of electron beam additive deposition with vertical feed of wire material...................... 6 Ilinykh A.S., Banul V.V., Vorontsov D.S. Theoretical analysis of passive rail grinding.................................. 22 Chinchanikar S. Modeling of sliding wear characteristics of Polytetrafl uoroethylene (PTFE) composite reinforced with carbon fi ber against SS304........................................................................................................ 40 EQUIPMENT. INSTRUMENTS Abbasov V.A., Bashirov R.J. Features of ultrasound application in plasma-mechanical processing of parts made of hard-to-process materials...................................................................................................................... 53 MATERIAL SCIENCE Stolyarov V.V., Andreev V.A., Karelin R.D., Ugurchiev U.Kh., Cherkasov V.V., Komarov V.S., Yusupov V.S. Deformability of TiNiHf shape memory alloy under rolling with pulsed current....................... 66 Vorontsov A.V., Filippov A.V., Shamarin N.N., Moskvichev E.N., Novitskaya O.S., Knyazhev E.O., Denisova Yu.A., Leonov A.A., Denisov V.V. Microstructure and residual stresses of ZrN/CrN multilayer coatings formed by the plasma-assisted vacuum-arc method........................................................................... 76 Ivanov I.V., Safarova D.E., Bataeva Z.B., Bataev I.A. Comparison of approaches based on the WilliamsonHall method for analyzing the structure of an Al0.3CoCrFeNi high-entropy alloy after cold deformation....... 90 Kryukov D.B. Structural features and technology of light armor composite materials with mechanism of brittle cracks localization.......................................................................................................................... 103 EDITORIALMATERIALS 112 FOUNDERS MATERIALS 123 CONTENTS
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 Structural features and technology of light armor composite materials with mechanism of brittle cracks localization Dmitry Kryukov* Penza State University, 40 Krasnaya st., Penza, 440028, Russian Federation https://orcid.org/0000-0003-0393-9550, ddbbkk@yandex.ru Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2022 vol. 24 no. 3 pp. 103–111 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2022-24.3-103-111 ART I CLE I NFO Article history: Received: 04 July 2022 Revised: 13 July 2022 Accepted: 21 July 2022 Available online: 15 September 2022 Keywords: Composite metal material Explosion welding Reinforcement Crack resistance Bullet resistance Acknowledgements Research were partially conducted at core facility “Structure, mechanical and physical properties of materials”. ABSTRACT Introduction. Monometallic armor traditionally used in military and special equipment armaments has a number of key disadvantages that have a signifi cant impact on the tactical and technical characteristics of the products, namely, signifi cant weight and thickness. At the same time, composite non-metallic armors, which have been widely used recently as an alternative, in turn, are not able to withstand multiple hits in local areas of the structure due to its complete destruction or delamination. The purpose of the work: to develop the technology of obtaining a new class of multilayer metal armor materials based on light metals and alloys by explosive welding, combining high indicators of bullet resistance and structural strength along with low specifi c gravity. The work presents a new scheme for reinforcing the composite using explosive welding technology, which allows localizing the development of brittle cracks along interlayer boundaries with external ballistic impact on the object. Results and discussion. Reinforced composite material based on titanium and aluminum alloys is obtained by explosive welding. Rational modes of shock-wave loading, which ensure production of composite material of required quality are determined; evaluation of strength of composite is carried out. In order to improve the tactical and technical characteristics of the composite, it was proposed to form high-solid intermetallic layers in its structure due to heat treatment. Rational modes of high-temperature annealing are defi ned, which ensure formation of intermetallic layers of preset thickness in composite structure. The phase composition of intermetallic pro-layers is studied. Structural features of the composite material are investigated. Mechanism of brittle cracks localization in composite structure at ballistic impact on it is described. For citation: Kryukov D.B. Structural features and technology of light armor composite materials with mechanism of brittle cracks localization. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2022, vol. 24, no. 3, pp. 103–111. DOI: 10.17212/1994-6309-2022-24.3-103-111. (In Russian). ______ * Corresponding author Kryukov Dmitry B., Ph.D. (Engineering), Associate Professor Penza State University 40 Krasnaya st., 440028 Penza, Russian Federation Тел.: 8 (8412) 666 262, e–mail: ddbbkk@yandex.ru Introduction Traditionally used in armour systems, steel and composites have its own highly specifi c applications. Armored products made of high-strength steel have proven itself as the basis for heavy armored vehicles, while armor based on composite materials is widely used for light armored vehicles, aviation equipment, combat robots and personal protective equipment [1–4]. Composites are most often used in cases where the weight of the armour is of critical importance. According to a number of experts [5–8], when replacing steel with a composite, it is possible to achieve a reduction in the weight of the product by about half, which in turn will increase equipment and improve the tactical and technical characteristics of the machine or product. Today, aramide, carbon and glass fi bers, ceramics, as well as polyethylene with a complex of various binding materials are widely used as a basis for light composite armor. At the same time, the technology
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 of manufacturing armored elements based on such materials requires the use of rather complex technical solutions and expensive equipment. The armor elements itself based on the above composites having ballistic characteristics comparable to monometallic armor do not compete with it at the requirement of multi-impact, i.e. are not able to withstand multiple hits in local areas due to complete destruction or delamination [7, 9, 14–16]. The development of a new class of composite armor materials that combine high bullet resistance and structural strength along with low specifi c gravity is an urgent task. The Department of Welding, Foundry and Materials Science, FSBEI HE Penza State University has developed a unique technology for the manufacture reinforced composite armor materials based on light metals and alloys that does not have analogues [10, 11]. The metal base of these materials is proposed to use an armored aluminum alloy (V95), and as reinforcing layers of titanium alloy (VT1-0). The metal composite is made using explosive welding technology, which allows obtaining high-quality welded joints of materials and alloys that cannot be welded by traditional methods, which include the above materials. Permanent metal joints obtained by the explosive welding technology are formed at the interatomic level without signifi cant thermal embedding in the contact zone of materials. The strength of the welded joint itself is higher than the strength of the least strong metal of the composition [19]. The purpose of this work is to develop a technology for obtaining a new class of multilayer metal armor materials based on light metals and alloys by explosive welding, combining high rate of bullet resistance and structural strength along with low specifi c gravity. This position will signifi cantly improve the tactical and technical characteristics of the armoured military weapons and special-purpose products. The objectives of the study are to develop a new reinforcing scheme for composite metal materials based on light metals and alloys; to determine rational modes of shock-wave loading, which ensure the production of composite material of the required quality by explosive welding; to describe the mechanism for brittle cracks localizing in the composite structure under ballistic impact on it. Research methodology In the composite reinforcing scheme special perforated layers made of titanium alloy are used (Fig. 1) [12]. The composite may contain two or more such layers. The perforations are arranged so that each subsequent layer does not coincide with the previous perforations and overlap is ensured. This nature of the arrangement of perforations in the composite structure does not allow a possible through passage of a ballistic object. Fig. 1. Perforated reinforcing layer
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 Fig. 2. Explosive Welding Diagram: 1 – electric detonator; 2 – container with explosive substance; 3 – driver plate; 4 – intermediate plate; 5 – fi xed plate; 6 – metal base; 7 – ground Predicated on the analysis of technological schemes of composite metal materials formation using explosive welding (V95 + VT1-0 + V95 + VT1-0 + V95) the plane-parallel scheme of welding by explosion submitted in Fig. 2 was chosen. The thickness of the sheets being weld (V95 + VT1-0 + V95 + VT1-0 + V95) was 2 + 1 + 2 + 1 + + 10 mm respectively. An explosive «Igdanite» (96:4 mixture of ammonium nitrate and diesel fuel) was used for welding. Explosive welding was carried out in a wide range of contact point speeds from 1,800 m/s to 2,400 m/s. Results and discussion According to the results of visual and dimensional and ultrasonic examination of the welded composite samples, the mode with the following technological parameters was chosen as the rational mode of explosion welding: explosive height 55 mm, contact point speed 2,200 m/s, gap between sheets being weld 2 mm. The criteria for choosing a rational mode of explosive welding were the absence of edge and internal unwelded spots in the composite, as well as the external state of its surface. In particular, it was found by the above control methods that in explosive welding modes with a contact point speed of less than 2,200 m/s, there was no welding of the layers in the edge region of the composite with partial cutting of the driver elements. The state of the composite welded at a contact point speed of more than 2,200 m/s was characterized by partial destruction of its surface with a large number of internal unwelded spots. Analysis of the macrostructure of the composite welded on the selected rational mode indicates a high quality of the material connection along the interlayer boundaries; the weld of the composite material along all interlayer boundaries is mainly wave-free. The appearance of the reinforced composite macrostructure after explosive welding is shown in Fig. 3. The role of perforations in the proposed circuit solution consists in the formation of a viscous homogeneous layer of a metal base of an aluminum alloy composite matrix, which presents a welded joint through the perforation of the reinforcing element. Upon contact with the ballistic object 1, brittle cracks arise in the composite, spread from the contact point 3 along the interlayer Fig. 3. Macrostructure of reinforced composite material based on light metals and alloys
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 boundaries 2, reaching the point of transition from the perforation edge to the welding zone of the composite viscous metal base 4, stop on it and the development of the brittle crack stops. This makes it possible to localize the zone of ballistic destruction of composite armor within the local zone of welding of aluminum and titanium layers 2, preserving the integrity of the product structure and its complex bullet resistance without obligatory replacement with a new armor element. Diagram of brittle crack localization in composite structure at contact with a ballistic object is given in Fig. 4. Fig. 4. Diagram of brittle cracks localization in the composite structure Fig. 5. Dependence of growth of intermetallic layer thickness on furnace holding time In addition, the presence of thin perforated layers in the structure of the metal composite material also contributes to an increase in its strength indicators [17]. Evaluation of strength parameters and preparation of the test samples were carried out according to the standard method in accordance with GOST 1497–84. A set of studies has shown that the best combination of physical and mechanical properties, such as strength and elongation, is possessed by samples welded at the selected rational mode. Its relative elongation was from 3.1 to 3.7 %, and the strength value was in the range from 570.2 to 594.1 MPa. Provided that the strength of the composite metal matrix base of similar thickness was in the order of 482.1–489.8 MPa, the total increase in the strength of the composite compared to it was 21.3 % [18, 20]. In order to improve the tactical and technical characteristics of the composite armor materials being developed on the basis of light metals and alloys, the authors proposed the formation of highsolid intermetallic layers in the composite structure due to heat treatment. Intermetallic layers are formed due to mutual thermal diffusion of metals included in composite at interlayer boundaries. Maximum thickness of intermetallic layers is controlled by parameters of heat treatment, namely temperature and time of soaking during annealing. A set of studies made it possible to establish the dependence of the growth of the intermetallic layers thickness on the soaking time; the results are shown in Fig. 5. Analysis of the obtained data indicates that the maximum thickness of the intermetallic layer is approximately 90–100 μm, while the holding time at a temperature of 625°C is approximately 300 hours.
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 The subsequent longer soaking of the material in the furnace does not lead to the growth of the intermetallic layer, which is apparently due to the ultimate extinction of diffusion processes. The formation of intermetallic interlayers along the weld of the composite armored material after heat treatment is shown in Fig. 6. X-ray phase analysis of intermetallic interlayers on a DRON3M diffractometer showed its composition corresponding to intermetallic TiAl3 [13]. The phase composition of the composite depending on the furnace holding time is shown in Fig. 7. The highly solid intermetallic layers (TiAl3) in the composite armor structure 2 contribute to the destruction of the ballistic object 1 into smaller parts, signifi cantly reducing its kinetic energy, and the highly viscous aluminum layers of the composite effectively retain the formed fragments 5 of the ballistic object. The scheme of composite armor operation in the presence of intermetallic layers is shown in Fig. 8. The mechanism of brittle cracks localization in the structure of a composite with intermetallic layers during ballistic impact on it is similar to that described above. Upon contact with the ballistic object 1, brittle cracks arising in it are formed and developed mainly in high-solid intermetallic layers 2 located along the aluminum-titanium welding zone. Spreading from the point of contact with the ballistic object 3 and reaching the point of transition from the edge of the perforation to the welding zone of the composite viscous metal base 4, the cracks stop on it, and its propagation stops (Fig. 8). Evaluation of the strength of the composite in the state after heat treatment showed its increase in the range from 610.7 to 633.8 MPa, however, there is a slight decrease in plasticity, characterized by relative elongation in the range from 2.1 to 2.7 %. Fig. 6. Microstructure of reinforced composite material based on light metals and alloys after heat treatment ×100 Fig. 7. The phase composition of the composite after annealing at a temperature of 625°C with different furnace holding time
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 24 No. 3 2022 Fig. 8. Diagram of composite armor operation in the presence of intermetallic layers in it Prototypes of new composite armor materials based on light metals and alloys developed by the authors of the work during ballistic tests confi rmed the high level of properties declared by the authors and compliance with the high class of protective structure of the EBP according to GOST R 51112–97 and GOST 34282–2017. Conclusions 1. An analysis of the scientifi c and technical literature showed that the traditionally used monometallic armor has a number of key disadvantages that affect the tactical and technical characteristics of the products, namely, signifi cant weight and thickness. It is noted that composite non-metallic armor, in turn, is not able to withstand multiple hits in local areas of the structure due to its complete destruction or delamination. 2. A new scheme of composite reinforcing using explosive welding technology is presented, which allows localizing the development of brittle cracks along interlayer boundaries with external ballistic impact on the object. 3. Reinforced composite material based on titanium and aluminum alloys is obtained by explosive welding. Rational modes of shock-wave loading are determined, which ensure production of composite material of required quality; evaluation of strength of composite is carried out. In order to improve the tactical and technical characteristics of the composite, it was proposed to form high-solid intermetallic layers in its structure due to heat treatment. 4. Rational modes of high-temperature annealing are defi ned, which ensure formation of intermetallic layers of preset thickness in composite structure. The phase composition of intermetallic interlayers was investigated. Mechanism of localization of brittle cracks in composite structure at ballistic action on it is described. The obtained results indicate the prospects of the proposed composite material reinforcing scheme using explosive welding and the manufacture of new types of armor materials based on it for a wide range of products, which combine high bullet resistance and structural strength along with low specifi c gravity. References 1. Bhatnagar A., ed. Lightweight ballistic composites: military and law-enforcement applications. 2nd ed. Amsterdam, Woodhead Publishing is an imprint of Elsevier, 2016. 482 p. DOI: 10.1016/C2014-0-03657-X. 2. Ma Z.D. Lightweight composite armor. Patent US, no. 0089597, 2007. 3. Gruber U., Heine M., Kienzle A., Nixdorf R. Armored products made of fi ber reinforced composite material with ceramic matrix. Patent US, no. 6709736, 2004. 4. Strasser T.E., Atmur S.D. Fiber reinforced ceramic matrix composite armor. Patent US, no. 6314858 V1, 2001. 5. Chen X., ed. Advanced fi brous composite materials for ballistic protection. 2nd ed. Amsterdam, Woodhead Publishing is an imprint of Elsevier, 2016. 548 p. DOI: 10.1016/C2014-0-01733-9.
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