Vol. 25 No. 4 2023 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. 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 Journal “Obrabotka Metallov – Metal Working and Material Science” is indexed in the world's largest abstracting bibliographic and scientometric databases Web of Science and Scopus. 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.
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 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 Aff airs, 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. Korotkov, D.Sc. (Engineering), Professor, Kuzbass State Technical University, Kemerovo; 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. 25 No. 4 2023 5 CONTENTS OBRABOTKAMETALLOV TECHNOLOGY Akintseva A.V., Pereverzev P.P. Modeling the interrelation of the cutting force with the cutting depth and the volumes of the metal being removed by single grains in fl at grinding........................................................................................................................................ 6 Sharma S.S., Joshi A., Rajpoot Y.S. A systematic review of processing techniques for cellular metallic foam production................. 22 Karlina Yu.I., Kononenko R.V., Ivantsivsky V.V., Popov M.A., Deryugin F.F., Byankin V.E. Review of modern requirements for welding of pipe high-strength low-alloy steels.......................................................................................................................................... 36 Startsev E.A., Bakhmatov P.V. The infl uence of automatic arc welding modes on the geometric parameters of the seam of butt joints made of low-carbon steel, made using experimental fl ux......................................................................................................................... 61 Martyushev N.V., Kozlov V.N., Qi M., Baginskiy A.G., Han Z., Bovkun A.S. Milling martensitic steel blanks obtained using additive technologies................................................................................................................................................................................ 74 Loginov Yu.N., Zamaraeva Yu.V. Evaluation of the bars’ multichannel angular pressing scheme and its potential application in practice................................................................................................................................................................................................... 90 EQUIPMENT. INSTRUMENTS Rajpoot Y.S., SharmaA.K., Mishra V.N., Saxena K., Deepak D., Sharma S.S. Eff ect of tool pin profi le on the tensile characteristics of friction stir welded joints of AA8011.................................................................................................................................................... 105 Chinchanikar S., Gadge M.G. Performance modeling and multi-objective optimization during turning AISI 304 stainless steel using coated and coated-microblasted tools........................................................................................................................................................ 117 Ghule G.S., Sanap S., Chinchanikar S. Ultrasonic vibration-assisted hard turning of AISI 52100 steel: comparative evaluation and modeling using dimensional analysis........................................................................................................................................................ 136 Pivkin P.M., Ershov A.A., Mironov N.E., Nadykto A.B. Infl uence of the shape of the toroidal fl ank surface on the cutting wedge angles and mechanical stresses along the drill cutting edge...................................................................................................................... 151 MATERIAL SCIENCE Sokolov R.A., Muratov K.R., Venediktov A.N., Mamadaliev R.A. Infl uence of internal stresses on the intensity of corrosion processes in structural steel....................................................................................................................................................................... 167 Klimenov V.A., Kolubaev E.A., Han Z., Chumaevskii A.V., Dvilis E.S., Strelkova I.L., Drobyaz E.A., Yaremenko O.B., Kuranov A.E. Elastic modulus and hardness of Ti alloy obtained by wire-feed electron-beam additive manufacturing................... 180 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. In situ crystal lattice analysis of nitride single-component and multilayer ZrN/CrN coatings in the process of thermal cycling.......................................................................................................................................................................................... 202 Rubtsov V.E., Panfi lov A.O., Kniazhev E.O., Nikolaeva A.V., Cheremnov A.M., Gusarova A.V., Beloborodov V.A., Chumaevskii A.V., Grinenko A.V., Kolubaev E.A. Infl uence of high-energy impact during plasma cutting on the structure and properties of surface layers of aluminum and titanium alloys................................................................................................................... 216 Bobylyov E.E., Storojenko I.D., Matorin A.A., Marchenko V.D. Features of the formation of Ni-Cr coatings obtained by diff usion alloying from low-melting liquid metal solutions..................................................................................................................................... 232 Burkov А.А., Konevtsov L.А., Dvornik М.И., Nikolenko S.V., Kulik M.A. Formation and investigation of the properties of FeWCrMoBC metallic glass coatings on carbon steel.......................................................................................................................... 244 Sharma S.S., Khatri R., Joshi A. A synergistic approach to the development of lightweight aluminium-based porous metallic foam using stir casting method........................................................................................................................................................................... 255 Strokach E.A., Kozhevnikov G.D., Pozhidaev A.A., Dobrovolsky S.V. Numerical study of titanium alloy high-velocity solid particle erosion.......................................................................................................................................................................................... 268 EDITORIALMATERIALS 284 FOUNDERS MATERIALS 295 CONTENTS
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology Milling martensitic steel blanks obtained using additive technologies Nikita Martyushev 1, a, *, Victor Kozlov 1, b, Mengxu Qi 1, c, Andrey Baginskiy 1, d, Zeli Han 1, e, Aleksandr Bovkun 2, f 1 National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk, 634050, Russian Federation 2 Irkutsk National Research Technical University, 83 Lermontova st., Irkutsk, 664074, Russian Federation a https://orcid.org/0000-0003-0620-9561, martjushev@tpu.ru; b https://orcid.org/0000-0001-9351-5713, kozlov-viktor@bk.ru; c https://orcid.org/0000-0003-3738-0193, mensyuy1@tpu.ru; d https://orcid.org/0000-0002-1544-6406, bagin@tpu.ru; e https://orcid.org/0000-0001-6502-6541, hanzelizy@gmail.com; f https://orcid.org/0000-0002-0623-4284, Bovas87@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. 2023 vol. 25 no. 4 pp. 74–89 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2023-25.4-74-89 ART I CLE I NFO Article history: Received: 14 July 2023 Revised: 24 July 2023 Accepted: 11 October 2023 Available online: 15 December 2023 Keywords: Electron-beam surfacing Additive technologies Martensitic stainless steel Cutting forces Processing modes Milling Funding This research was supported by TPU development program. Acknowledgements Research were partially conducted at core facility “Structure, mechanical and physical properties of materials”. ABSTRACT Introduction. In recent years, more attention has been paid to additive wire printing technologies. Due to the peculiarities of printing with wire, the hardness of the workpiece is significantly higher than with traditional forging. An increase in hardness leads to an increase in cutting force. The aim of the work is to study the cutting force during milling workpieces of stainless steel 0.4 C-13 Cr obtained by electron-beam surfacing. Research Methods The specimens were obtained by surfacing wire from martensitic stainless steel 0.4 C-13 Cr. The microstructure of the specimens was studied in this work. The main attention was paid to the study of cutting forces during the processing of specimens. The work investigate specimens obtained by electron-beam surfacing with 0.4 C-13 Cr steel wire. The cutting forces arising during milling of these specimens are determined. To carry out the research work, a standard methodology for conducting experiments to determine cutting forces was chosen. However, to determine the forces Pz and Py, a fourflute (z = 4) milling cutter was used and the milling width was less than 2 mm. Results and discussion. The structure of the specimens obtained by electron-beam surfacing is tempered martensite. It is established that high-speed milling, high-efficiency milling and conventional milling are suitable for processing such workpieces. For processing thin-walled workpieces made of martensitic stainless steel after its manufacture by the method of electron-beam surfacing, it is necessary to use only carbide cutters with a diameter of at least 12 mm. The cutting modes obtained in the study make it possible to reduce the temperature of the cutting edge, cutting force and bending of a low-rigid end mill. So, in the course of the study, it was possible to select modes that reduce the vibration of the machine-device-tool-part system. For citation: Martyushev N.V., Kozlov V.N., Qi M., Baginskiy A.G., Han Z., Bovkun A.S. Milling martensitic steel blanks obtained using additive technologies. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2023, vol. 25, no. 4, pp. 74–89. DOI: 10.17212/1994-6309-2023-25.4-74-89. (In Russian). ______ * Corresponding author Martyushev Nikita V., Ph.D. (Engineering), Associate Professor National Research Tomsk Polytechnic University, 30 Lenin Avenue, 634050, Tomsk, Russian Federation Tel.: +7 (3822) 60-62-85, e-mail: martjushev@tpu.ru Introduction The development of science and industry leads to the emergence and active development of new technologies. Such technologies are also emerging in the area of the processing and manufacturing of metal parts and blanks. One of the promising modern technologies used for manufacturing parts is additive technology. Additive technologies do not have very high productivity; the cost of manufacturing parts using this technology is also quite high. One of the directions in the development of additive technologies is the
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 printing of specimens using metal surfacing. This technology significantly reduces the production time of the workpiece and reduces the cost of its production. This is due to the fact that instead of powder, surfacing wire is used during printing, the cost of which is significantly lower. However, a significant disadvantage of printed specimens is the low quality of the surface and such specimens require additional machining. Due to the peculiarity of this technology associated with the cooling of printed parts, its hardness is higher than when using forging or casting. This is especially evident when manufacturing parts made of martensitic stainless steels. These steels are quite inexpensive and are widely used, including for surfacing. When forming a part using a layer-by-layer surfacing, a new layer is applied to the previous one. The previous one is reheated and quickly cooled again. Since the critical cooling rate of martensitic steels is not high, a martensitic structure of high hardness is formed. The research conducted by the authors in [2, 3] confirms this fact. The layer-by-layer laser surfacing of the powder imparts different mechanical properties throughout the cross-section of the printed workpieces. The grain size, porosity and, accordingly, mechanical properties depend on the direction in which it is measured. In [4], the authors also showed that the properties of the products printed using additive technologies are different in different directions. The authors also showed that this could be partially corrected by heat treatment. Nevertheless, such correction requires additional costs for an additional operation. Similar results are shown in [5] demonstrating that thermal cycling of individual areas during printing may initiate internal stresses occurrence within the printed workpiece. The work [5] states that a hard-to-process crust (750 HV) was formed on the surface of 0.4 % C-13 % Cr steel specimens during SLM. When printing with wire (WAAM), the bottom layer recrystallizes while the next layer is applied to it. In this case, a structure, consisting of elongated grains of ferrite and fine-grained acicular martensite, is formed in the matrix upper layer. This structure is formed instead of the spatial periodicity of martensite laths within equiaxed ferrite grains in the inner layers. The martensite content gradually increases proportionally to the distance from the base metal [6]. The operating equipment conditions largely determine the process of forming a workpiece using the wire surfacing. These are parameters such as the temperature of the substrate, the trajectory of movement [7], etc. However, even under optimal conditions, various defects in the structure of the material may still appear (surface hardening, inhomogeneity, etc.). The WAAM technology is one of the additive technologies. When printing workpieces using the WAAM technology, the workpieces with heterogeneous structure and mechanical properties are also obtained. Another disadvantage of the WAAM technology is a poor surface quality. After the workpiece is manufactured, subsequent machining is required to obtain the desired geometric tolerances and surface properties [8]. When machining such workpieces, it is necessary to consider these features. Processing of workpieces obtained from stainless steels using the WAAM method on a milling machine is possible with fairly high productivity [9]. However, a significant tool wear is observed when milling the WAAM part. This occurs despite the fact that the tool and milling parameters were selected based on the manufacturer’s recommendations intended for processing a given material. The heterogeneous microstructure formed in the specimen obtained by the WAAM technology leads to a significant deterioration in its machinability. This is due to complex thermal cycles occurring during printing. The authors of [10] demonstrated the difficulties that arise when milling the Ti6Al4V alloy with an Al2O3/Si3N4 (sialon) end mill. The authors noted a more significant tool wear when machining the WAAM specimens as compared to forged and cast ones. The wear can be reduced and the tool life may increase by changing the cutting speed and feed [11, 12]. The cryogenic cooling of the cutting tool can also be used. Another way to reduce the tool wear is to select printing modes that enable the desired surface properties. To overcome the hardness heterogeneity of the printed workpiece, a methodology intended for segregating microhardness data into individual assemblies was developed and tested [13, 14]. Combining various additive printing technologies allows obtaining a more uniform structure. But in general, researchers [15] note that when processing printed workpieces, cutting forces increase in comparison with those of the workpieces produced by traditional methods. The authors of [16] stated that the workpieces produced by additive technologies possessed completely different cutting forces under the same processing conditions.
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology Down milling is recommended for processing the parts made of the 316L steel produced by laser additive technologies (LAM) [17, 18]. It provides a better surface quality in terms of roughness compared to that of counter-production. Tool wear can be reduced and machining productivity can be increased using ultrasonic vibration milling during down milling [19–23]. At the same time, the work is currently underway to combine additive and subtractive technologies using the same equipment [24]. This improves the manufacturing accuracy, reduces the operating time and tool wear. The importance of determining the optimal processing modes of workpieces obtained by additive wire printing methods is noted in [25]. Moreover, the standard processing modes are reported not to provide optimal results. In general, the authors of [25–28] also suggest that different positions of the workpiece during 3D printing generate different properties during printing. The vertically manufactured workpieces are cooled more slowly than the horizontally located ones. As a result, depending on the workpiece location during printing, its properties will be different. This will also affect the processing modes. Therefore, when assigning subtractive processing modes, it is important to know the workpiece manufacturing specifics. This will directly affect the quality of processing and tool wear. This is especially important for the parts made by electron-beam printing (EBW). The printing blanks using the WAAM method is more widespread due to its low cost. The EBW method produces more precise and critical parts. Such parts should have higher accuracy. Therefore, for workpieces manufactured by the EBW method, it is extremely important to study the features of subsequent retractive processing. An analysis of the literature shows that there are works devoted to the properties of differently oriented printed specimens. Nevertheless, there are practically no works showing how much these changes in properties for differently oriented printed specimens affect the modes of subtractive processing. There are practically no works devoted to the processing of the workpieces printed using the EBW method. There are very few works devoted to the subtractive processing of the workpieces obtained by electronbeam printing. Therefore, the topic of selecting optimal modes of processing the workpieces manufactured using WAAM (wire surfacing) methods is very relevant. The aim of this work is to use the experimental work to determine the patterns of changes in forces when milling the workpieces made of the stainless steel 0.4 % C-13 % Cr, manufactured by electron-beam surfacing. Materials and methods To conduct the research on milling, specimens were obtained using the electron-beam wire surfacing technology. 10 specimens were printed for the research. 5 specimens were used for down milling and 5 specimens underwent up milling. The dimensions of the specimens were 14×70×15 mm (height × width × length). The specimens under study were printed using steel wire, the chemical composition of which is given in Table 1. Ta b l e 1 The chemical composition of martensitic steel C Mn Si Ni Cr P S Fe 0.40 0.49 0.54 0.50 13.1 0.020 0.016 balance Manufacture of the specimens using an electron beam installation The specimens were printed using an electron-beam (EBW) wire surfacing machine. The installation was developed and manufactured at Tomsk Polytechnic University (fig. 1). The accelerating voltage of the EBW installation is 40 kV and it remains unchanged. The current variation range is 0–200 mA. The initial material intended for producing a workpiece using the EBW method is the stainless steel 0.4 % C-13 % Cr wire with a diameter of 1.2 mm. The general scheme for printing the specimens is shown in fig. 2.
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 When printing the specimens, the following modes were used: ● circular beam scan: 3.0–5.0 mm; ● wire feed angle: 45.0°; ● beam current: 30 mA; ● wire feed speed: 700 mm/min. When printing, the same material was used as the substrate material as for the wire – stainless steel 0.4 % C-13 % Cr. Printing was carried out in a vacuum at pressure 5×10−3 Pa. The study of the microstructure of the obtained specimens The microstructure of the specimens was detected using an etchant. Its composition was a mixture of concentrated nitric HNO3 (67 wt. %) and hydrochloric HCl (33 wt. %) acids. The ratio of acids was 1:3 by volume. The microstructure was studied using a MMP-1 microscope (BIOMED). Study of cutting forces during milling An CNC machine CONCEPTMill 155 (EMCO) was used to mill the specimens. Cutting forces were determined using a Kistler 9257B dynamometer (Switzerland). The directions of the measured forces Fx, Fy and Fz displayed on the monitor of the Kistler dynamometer, correspond to the forces Ph, Pv and Px during Fig. 1. General view of the working chamber of the electron-beam wire surfacing installation a b Fig. 2. Scheme for printing a specimen: pattern for printing one horizontal layer (a); print pattern in the vertical direction (b)
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology milling. In addition, the forces Fz, Fy approximately correspond to the tangential Pz and radial Pу forces during penetration and when the tooth leaves contact, if t is equal to half the cutter diameter To carry out the research work, a standard methodology used for conducting experiments to determine cutting forces was chosen. However, to determine the forces Pz and Py, we made a number of deviations from this technique. A four-flute (z = 4) cutter was used; the milling width was less than 2 mm. The milling depth t was slightly less (0.2 mm) than half the cutter diameter d (t ≈ 0.5∙d – 0.2). This deviation from the standard approach made it possible to calculate the components of the normal N and tangential F forces acting on the front surface of the cutter tooth using certain forces Pz and Py. In this case, the rake angle was taken into account. DynoWare software was used to analyze the data. The sensitivity of the dynamometer is 7.5 N, its measurement error is ±0.005 %. The scatter in measuring cutting forces was no more than 15 %. This error is due to the wear of the milling cutter. If there is wear, it is necessary to make a reconfiguration. However, it is very difficult to ensure the accuracy of the adjustment to the required width and depth of milling, even with a slight wear of the cutter during experiments. Carbide end mills produced by GESAC (China) were chosen as the tool. The hard alloy consisted mainly of tungsten carbides and a cobalt binder (~8 %). Its parameters are given in table 2. The rear angle was 5º, the rake angle amounted to 7º. We used cutters covered with a coating, the characteristics of which are given in table 3. The choice of the cutters with such a coating is determined by the processing conditions. In the experiments we used up and down dry milling. Down milling was carried out with a 4-tooth cutter of d = 8 mm, milling width of which was B = 2 mm, the spindle speed was n = 500 rpm, the feed was sm = 104 mm/min. A large feed value was chosen in order to test the selected tool in extreme operating conditions. Up milling was also carried out with a 4-tooth cutter of d = 8 mm at B = 2 mm, n = 500 rpm, sm = 28 mm/min. When choosing cutting modes, we proceeded from the experience of the work performed by the authors in [28]. Ta b l e 2 The main parameters of the milling cutters used Factory marking Coating Diameter, D, mm Helical flute angle, ω, ° Number of teeth, z UP210-S4-08020 AlCrSiN 8 35 4 Ta b l e 3 The main parameters of the coating of the milling cutters used Coating HV0.05 μ T AlCrSiN 3,300 0.4 1,100 Results and discussion Obtaining specimens by electron-beam surfacing and studying its microstructure At the first stage of the work, we prepared specimens intended for subsequent machining. Since the technology used for printing specimens by means of an electron beam by surfacing the wire is quite new, there are practically no standard modes for producing specimens. Printing modes are mainly depend on the material being printed and the geometric dimensions of the specimens. We presented the technology for selecting the printing modes for the stainless steel 0.4 % C-13 % Cr in more detail in [28]. The beam current value was ranging within some limit to determine the optimal printing modes. During the experiments, 6 different beam current values were used. The value at which the highest quality specimen was obtained gaining the fewest defects and a smooth surface was then used to obtain the remaining specimens.
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 Manufacturing the specimens using electron-beam surfacing In this work, 5 experimental specimens were printed using the electron-beam 3D wire printing technology. As a result of the preliminary work, the optimal value of the beam current was determined to be 30 mA (fig. 3). Fig. 3. A specimen obtained by electron-beam surfacing with a 0.4 C-13 Cr steel wire The first printed layer has the fastest cooling rate. If the beam current is too high, this leads to the meltthrough of not only the wire, but also of the substrate material. As a result, a hole appears at the border of the printed specimen. Printing the next layer will not be possible. As the beam current decreases, the print path length increases. As the number of the printed layers increases, the cooling rate decreases and the overall temperature of the specimen increases. Based on this, when printing the specimens, the optimal printing modes were determined under which it was possible to form the workpiece layer by layer. This is a beam current of 30 mA and a wire feed of 700 mm/min [28]. Study of the microstructure of the printed specimens Traditional methods of forming blanks (forging, casting) ensure a completely martensitic structure for the stainless steel 0.4 % C-13 % Cr. When using additive technologies, austenite and δ-ferrite can form in such steel. In the course of our work, we studied the microstructure of steels. As shown in fig. 4, the printed specimens have a dense structure. There are no cracks at the interlayer boundaries and there is no boundary of the molten pool. The microstructure of the manufactured specimens is similar to the microstructure of the steel 0.4 % C-13 % Cr after quenching and low tempering [29–33]. Martensite has a needle-like structure. This behavior is attributed to the high cooling rate during solidification in electron-beam additive manufacturing, which facilitates the phase transformation of austenite to martensite. These randomly oriented martensitic needles are much smaller than the martensitic needles formed during the casting and quenching of stainless steel 0.4 % C-13 % Cr [26, 27]. When additively printing a specimen, the heat coming from the applied new layer affects the previously printed ones. The underlying layers below the printed layer are heated above the austenitizing temperature. The previously formed martensite transforms into austenite and, after cooling, retained austenite and martensite form again. However, if the temperature is insufficient and below the austenitization temperature, then the process of martensite tempering occurs, the retained austenite again turns into martensite.
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology a b Fig. 4. Microstructure of the specimens: the area near the edge of the specimen (a); the central part of the specimen (b) Study of cutting forces when machining the specimens At the third stage of our work, we conducted a study of the cutting forces arising during milling of the printed specimens. When processing the printed specimens, the greatest attention in this work was paid to the component forces Ph and Pv (fig. 5, 6). This is because the Px force is small relative to other forces. It is directed along the axis of the cutter. This is the direction of the highest rigidity of the cutter (fig. 6). The radial direction is the direction of the lowest rigidity used for the end mill. Based on this, the force Py acting radially on the cutter axis leads to vibration. During the study, we constructed graphs of changes occurring in the cutting forces during milling with a four-flute cutter for up and down milling processes. Up milling process When up milling with a four-tooth cutter having a diameter of 8 mm at t = 3.8 mm, the change in the components of the cutting forces as a function of time τ (s) is shown in fig. 7. The cutter diameter that is slightly less than 4 mm was taken to ensure that the next tooth had not yet started cutting. The graph shows the forces generated during one full revolution of the cutter. The curves of the main cutting force components Ph and Pv show four clear peaks. These peaks correspond to the work of each of the four cutter teeth. The force increases when the tooth cuts into the workpiece and the force decreases when the tooth leaves the cutting zone. a b Fig. 5. The direction scheme of the components of the cutting force in asymmetric up end milling with a four-tooth end mill with a diameter of d = 8 mm at a milling depth of t = d/2 – 0.2 mm = 3.8 mm: when tooth No.1 enters the workpiece (the previous tooth No.4 is already out of contact) (a); when tooth No.1 leaves contact with the workpiece (the next tooth No.2 has not yet come into contact with the workpiece) (b)
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 a b Fig. 6. The direction scheme of the components of the cutting force in asymmetric up end milling in the top view: the position of the cutter tooth at a central angle ψ ≈ 50º from the point of contact to the considered position (a); large diagram of the action of the components Pvi and Phi, as well as Pz and Py and its resulting Phvi and Pzy at ψ ≈ 50º (b) The axial component Px changes slightly throughout the entire cycle (fig. 7, the range is between numbers 1 and 5), because along the end part, three teeth are in contact with the workpiece almost immediately having a four-flute cutter and milling depth of t ≈ d/2 (fig. 5, a, b) when decreasing the milling depth of t < 0.2d. That is, if the milling depth t is less than the cutter flute depth h, only one tooth will be in constant contact with the workpiece. This will cause large changes in the value of the Px component as the cutter rotates. The operating time of one tooth is t = d/2 and a four-tooth cutter (z = 4) has τ1 tooth = 60/(4∙n) (s). The graph of changes in the magnitude of the components Ph Pv and Px of the cutting force (fig. 7) shows that there is a non-synchronous change in its value. When analyzing changes in the milling forces, one should keep in mind that the Kistler dynamometer is installed across the milling table (perpendicular to the longitudinal feed of the table sm), and the workpiece is installed with its long part across the dynamometer, i.e., parallel to the direction of the longitudinal feed of the table sm. The workpiece is behind the cutter when viewed from the operator’s side. When a tooth cuts into a workpiece (fig. 7, the range is between numbers 1 and 2), the cutter tooth with its rounded cutting edge pushes the workpiece away from the axis of rotation of the cutter. That means that a component force Pv cut appears with a negative sign (in the signal processing program using the Kistler dynamometer, the sensors are “wired” and the positive sign of the force Fy (Pv during milling) will be when the force is applied towards the operator, i.e. as in turning). At the same time, the component force Ph of the cut acts with a positive sign, i.e., the cutter tooth pushes the workpiece in the direction opposite to the direction of the counter feed sm (fig. 8). The positive sign of the force Fх (Ph during milling) on the monitor will be when the force is applied from left to right, i.e. as in turning. When the tooth rotates further (fig. 7, the range is between numbers 2 and 3), the force Pv acts in the positive direction of the OY axis. That is, the cutter tooth attracts the workpiece to the axis of rotation of the cutter due to the positive main rake angle γ (fig. 8, but the position of the cutter after the workpiece is Fig. 7. Graphs of force changes during milling when turning a sharp cutter for one revolution. Up milling with a 4-tooth cutter d = 8 mm, t = 3.8 mm, B = 2mm, n = 500 rpm, sm = 28mm/min, specimen No.1 – carbide
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology shown in the top view). The component force Ph continuously increases as the cutter tooth rotates, since the cut thickness ai = sz∙sinψi increases (fig. 7, the range is between numbers 2 and 3). As the cutter tooth rotates through an angle ψ, the cut thickness a increases, the direction of the components Pz and Py of the cutting force also changes (fig. 9, but the position of the cutter after the workpiece is shown in the top view). As the cut thickness a increases, the force Pz increases more intensively than the force Py does, since this component is “responsible” for cutting the chips. When the cut thickness increases, the force Py practically should not change including a sharp cutting wedge due to the low friction coefficient on the front surface of the cutter tooth. Changing the action direction of the forces Pz and Py when turning the cutter through an angle ψ leads to the fact that the component Pv increases. And the component Ph begins to decrease, on the contrary, due to the rotation of the greatest force Pz towards the OY axis, i.e. it increases the force Pv further instead of Ph (fig. 7, the range is between numbers 3 and 4). A further rotation of the cutter leads to a decrease in the cut thickness ai during the period when the tooth leaves contact with the workpiece, which causes a decrease in the components Pz and Py, and therefore the components Ph and Pv (fig. 7, the range is between numbers 4 and 5). The decrease in these components Fig. 8. Component forces acting on the workpiece during up milling with a sharp cutter (the position of the cutter after the workpiece is shown in the top view) Fig. 9. Force components (Py, Pz) obtained after decomposing the milling force (Ph, Pv) into a direction towards the cutter axis and a tangential direction, i.e. tangent to the direction of rotation of the cutter (the position of the cutter after the workpiece is shown in top view)
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 does not occur as quickly as the decrease in cut thickness does at the end of the cut with a tooth, because elastic deformation of the MDTP system (machine-device-tool-part) does not allow it to be as sharply as theoretically expected. We believe that with an increase in the MDTP system rigidity, and, above all, with an increase in the end mill rigidity as the most flexible element, there will be a more rapid decrease in the forces at the end of the cutter tooth operation. A negative value of the sign of the force Px (Px = -120…-170 N) indicates the desire of the cutter to lift the workpiece, which is associated with a positive inclination angle of the cutter teeth of ω = 40º. An increase of the force Px in the negative direction within the range of numbers 2–5 (fig. 7) is associated with an increase in the cut thickness when turning the cutter. Moreover, a decrease in the range of numbers 5–6 is associated with a decrease in the cut thickness at the end of the cycle of cutting the allowance with the tooth in question. During further rotation of the cutter, the next cutter tooth begins to cut into the workpiece, so the cycle of changing the component forces is repeated (fig. 7, the range is between numbers 5 and 9). Down milling process When cutting a tooth into the workpiece (fig. 10, the range is between numbers 1 and 2), the cut thickness a quickly increases to the maximum value amax, so the component force Ph quickly increases to the maximum value. And Pv also quickly increases in the negative direction of the OY axis of the dynamometer (the cutter, with its rounded cutting edge and its rear surface, pushes the workpiece away from the axis of the cutter). Since the feed rate sm = 104 mm/min is very high, i.e. the cut thickness a is large, the force Py acting in the radial direction towards the cutter axis also includes a normal load acting from the rear surface of the tooth when cutting-in. Under the influence of forces Py and Pz, the component Pv continues to increase in a negative direction due to the high feed and movement of the cutter tooth to continue cutting. Since the cut thickness decreases during down milling, the undercutting of the metal under the cutting edge increases, but not as intensely as it does during up milling because of the presence of chips on the front surface of the cutter tooth. On the contrary, the Ph component at this time begins to decrease due to a decrease in the slice thickness and, accordingly, a decrease in the force Pz, and in addition, it rotates towards the OY axis, i.e., it acts more on the force Pv, and not on the Ph (fig. 10, the range is between numbers 2 and 3). Further rotation of the cutter leads to a further reduction in the cut thickness a to zero, which causes a decrease in the components Pz and Py, and therefore the components Ph and Pv (fig. 10, the range is between numbers 3 and 4). Due to the elastic deformation of the MDTP system, under the influence of force Pv, the cutter is repelled from the machined surface, which is why the depth of cut does not reach the specified value, and, in turn, this leads to a reduction in the time of milling with one tooth of the workpiece. In fig. 10 in the range between the numbers 4 and 5 the forces are equal to zero. As well as the change in force, Px during up milling, Px during down milling fluctuate up and down depending on the change in the cutting thickness a, and these changes are small. A negative value of the sign of the force Px indicates the tendency of the cutter to lift the workpiece, which is associated with a positive angle of of the cutter teeth inclination ω = 40º. During further rotation of the cutter, the next cutter tooth begins to cut into the workpiece, so the cycle of changing the component forces is repeated (fig. 10, the range is between numbers 5 and 6). However, Fig. 10. Graphs of force changes during milling when turning a sharp cutter for one revolution. Down milling with a 4-tooth cutter d = 8 mm, t = 4 mm, B = 2 mm, n = 500 rpm, sm = = 104 mm/min, specimen No.1 – carbide
OBRABOTKAMETALLOV Vol. 25 No. 4 2023 technology due to the elastic deformation of the MDTP system and the slight radial runout of the teeth, the maximum force of each cycle is not the same. As a result of the experimental work, the forces acting on the tool when processing specimens from heat-resistant steel obtained by the EBW wire method are determined. Patterns of changes in cutting forces during cutting with one tooth are also obtained. Important results include determining the change in the direction of the lateral component of the cutting force Pv. Since the presence of a gap in the screw pair of the transverse feed of the machine leads to vibrations, it should be reduced to a minimum. Knowing the Ph feed force obtained from the results of the tests allows calculating the necessary workpiece clamping force. This is especially important when the workpiece has low rigidity. These results are important for manufacturing enterprises when processing workpieces obtained by the EBW wire method. Conclusion The cutting forces are studied by milling the rectangular specimens produced by electron-beam surfacing of the martensitic stainless steel. Based on the experiments, the following main conclusions are drawn: 1. The structure of the specimens printed by electron-beam surfacing corresponds to temperedmartensite. 2. The magnitude of the resulting cutting force Phv for up and down milling is almost the same. But the cutting force in the feed direction Ph during up milling is significantly greater than that taking place during down milling, and the lateral force Pv during up milling is significantly less than that arising during down milling. Based on the mentioned, when processing thin-walled parts, down milling should be used. 3. In this work, using a slight deviation from the standard method of measuring the cutting forces, the dependences of the changes in forces Pz and Py during the operation of the cutter are obtained. These data allow constructing diagrams of contact stresses involving known physical components on the front surface of the tooth. The standard methodology does not provide such data. This is especially important for the process of designing a new tool. This allows calculating the tool in terms of the work devoted to the stainless steel 0.4 % C-13 % Cr. The forces Pz and Py acting on the cutter tooth are determined. As a continuation of this work, it is planned to determine the forces Pz and Py for titanium alloys obtained by the EBW wire surfacing. References 1. Alvarez L.F., Garcia C., Lopez V. Continuous cooling transformations in martensitic stainless steels. ISIJ International, 1994, vol. 34 (6), pp. 516–521. DOI: 10.2355/isijinternational.34.516. 2. Kazemipour M., Lunde J.H., Salahi S., Nasiri A. On the microstructure and corrosion behavior of wire arc additively manufactured AISI 420 stainless steel. TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings. Springer, 2020, pp. 435–448. DOI: 10.1007/978-3-030-36296-6_41. 3. Liverani E., Fortunato A. Additive manufacturing of AISI 420 stainless steel: Process validation, defect analysis and mechanical characterization in different process and post-process conditions. The International Journal of Advanced Manufacturing Technology, 2021, vol. 117 (3–4), pp. 809–821. DOI: 10.1007/s00170-021-07639-6. 4. Saeidi K., Zapata D.L., Lofaj F., Kvetkova L., Olsen J., Shen Z., Akhtar F. Ultra-high strength martensitic 420 stainless steel with high ductility. Additive Manufacturing, 2019, vol. 29, p. 100803. DOI: 10.1016/j. addma.2019.100803. 5. Krakhmalev P., Yadroitsava I., Fredriksson G., Yadroitsev I. In situ heat treatment in selective laser melted martensitic AISI 420 stainless steels. Materials & Design, 2015, vol. 87, pp. 380–385. DOI: 10.1016/j. matdes.2015.08.045. 6. Ge J., Lin J., Chen Y., Lei Y., Fu H. Characterization of wire arc additive manufacturing 2Cr13 part: Process stability, microstructural evolution, and tensile properties. Journal of Alloys and Compounds, 2018, vol. 748, pp. 911– 921. DOI: 10.1016/j.jallcom.2018.03.222. 7. Manokruang S., Vignat F., Museau M., Limousin M. Process parameters effect on weld beads geometry deposited by Wire and Arc Additive Manufacturing (WAAM). Advances on Mechanics, Design Engineering and Manufacturing III. JCM 2020. Springer, 2021, pp. 9–14. DOI: 10.1007/978-3-030-70566-4_3. 8. GrzesikW. Hybrid additive and subtractive manufacturing processes and systems: a review. Journal of Machine Engineering, 2018, vol. 18 (4), pp. 5–24. DOI: 10.5604/01.3001.0012.7629.
OBRABOTKAMETALLOV technology Vol. 25 No. 4 2023 9. Lopes J.G., Machado C.M., Duarte V.R., Rodrigues T.A., Santos T.G., Oliveira J.P. Effect of milling parameters on HSLA steel parts produced by Wire and Arc Additive Manufacturing (WAAM). Journal of Manufacturing Processes, 2020, vol. 59, pp. 739–749. DOI: 10.1016/j.jmapro.2020.10.007. 10. Dang J., Zhang H., Ming W., An Q., Chen M. New observations on wear characteristics of solid Al2O3/Si3N4 ceramic tool in high speed milling of additive manufactured Ti6Al4V. Ceramics International, 2020, vol. 46 (5), pp. 5876–5886. DOI: 10.1016/j.ceramint.2019.11.039. 11. Bordin A., Bruschi S., Ghiotti A., Bariani P.F. Analysis of tool wear in cryogenic machining of additive manufactured Ti6Al4V alloy. Wear, 2015, vol. 328–329, pp. 89–99. DOI: 10.1016/j.wear.2015.01.030. 12. Milton S., MorandeauA., Chalon F., Leroy R. Influence of finish machining on the surface integrity of Ti6Al4V produced by selective laser melting. Procedia CIRP, 2016, vol. 45, pp. 127–130. DOI: 10.1016/j.procir.2016.02.340. 13. Keist J.S., Palmer T.A. Development of strength-hardness relationships in additively manufactured titanium alloys. Materials Science and Engineering: A, 2017, vol. 693, pp. 214–224. DOI: 10.1016/j.msea.2017.03.102. 14. Tascioglu E., Kaynak Yu., Poyraz Ö., Orhangül A., Ören S. The effect of finish-milling operation on surface quality and wear resistance of Inconel 625 produced by selective laser melting additive manufacturing. Advanced Surface Enhancement. INCASE 2019. Springer, 2020, pp. 263–272. DOI: 10.1007/978-981-15-0054-1_27. 15. Montevecchi F., Grossi N., Takagi H., Scippa A., Sasahara H., Campatelli G. Cutting forces analysis in additive manufactured AISI H13 alloy. Procedia CIRP, 2016, vol. 46, pp. 476–479. 16. Hojati F., Daneshi A., Soltani B., Azarhoushang B., Biermann D. Study on machinability of additively manufactured and conventional titanium alloys in micro-milling process. Precision Engineering, 2020, vol. 62, pp. 1–9. DOI: 10.1016/j.precisioneng.2019.11.002. 17. Gong Y., Li P. Analysis of tool wear performance and surface quality in post milling of additive manufactured 316L stainless steel. Journal of Mechanical Science and Technology, 2019, vol. 33, pp. 2387–2395. DOI: 10.1007/ s12206-019-0237-x. 18. Ni Ch., Zhu L., Yang Zh. Comparative investigation of tool wear mechanism and corresponding machined surface characterization in feed-direction ultrasonic vibration assisted milling of Ti–6Al–4V from dynamic view. Wear, 2019, vol. 436, p. 203006. DOI: 10.1016/j.wear.2019.203006. 19. Xiong X., Haiou Z., Guilan W. A new method of direct metal prototyping: hybrid plasma deposition and milling. Rapid Prototyping Journal, 2008, vol. 14 (1), pp. 53–56. DOI: 10.1108/13552540810841562. 20. Ahmetshin R., Fedorov V., Kostikov K., Martyushev N., Ovchinnikov V., Rasin A., Yakovlev A. SLS setup and its working procedure. Key Engineering Materials, 2016, vol. 685, pp. 477–481. DOI: 10.4028/www.scientific. net/KEM.685.477. 21. Martyushev N., Petrenko Yu. Effects of crystallization conditions on lead tin bronze properties. Advanced Materials Research, 2014, vol. 880, pp. 174–178. DOI: 10.4028/www.scientific.net/AMR.880.174. 22. Isametova M.E., Martyushev N.V., Karlina Y.I., Kononenko R.V., Skeeba V.Yu., Absadykov B.N. Thermal pulse processing of blanks of small-sized parts made of beryllium bronze and 29 NK alloy. Materials, 2022, vol. 15, p. 6682. DOI: 10.3390/ma15196682. 23. Martyushev N.V., Bublik D.A., Kukartsev V.V., Tynchenko V.S., Klyuev R.V., Tynchenko Y.A., Karlina Y.I. Provision of rational parameters for the turning mode of small-sized parts made of the 29 NK alloy and beryllium bronze for subsequent thermal pulse deburring. Materials, 2023, vol. 16, p. 3490. DOI: 10.3390/ma16093490. 24. Cahoon B.W.H., Broughton W.H., Kutzak A.R. The determination of yield strength from hardness measurements. Metallurgical Transactions, 1971, vol. 2 (7), pp. 1979–1983. DOI: 10.1007/bf02913433. 25. Abootorabi Zarchi M.M., Razfar M.R., Abdullah A. Influence of ultrasonic vibrations on side milling of AISI 420 stainless steel. The International Journal of Advanced Manufacturing Technology, 2013, vol. 66, pp. 83– 89. DOI: 10.1007/s00170-012-4307-9. 26. Lou X., Andresen P.L., Rebak R.B. Oxide inclusions in laser additive manufactured stainless steel and their effects on impact toughness and stress corrosion cracking behavior. Journal of Nuclear Materials, 2018, vol. 499, pp. 182–190. DOI: 10.1016/j.jnucmat.2017.11.036. 27. Chen X., Li J., Cheng X., Wang H., Huang Z. Effect of heat treatment on microstructure, mechanical and corrosion properties of austenitic stainless steel 316L using arc additive manufacturing. Materials Science and Engineering: A, 2018, vol. 715, pp. 307–314. DOI: 10.1016/j.msea.2017.10.002. 28. Martyushev N.V., Kozlov V.N., Qi M., Tynchenko V.S., Kononenko R.V., Konyukhov V.Y., Valuev D.V. Production of workpieces from martensitic stainless steel using electron-beam surfacing and investigation of cutting forces when milling workpieces. Materials, 2023, vol. 16, p. 4529. DOI: 10.3390/ma16134529.
RkJQdWJsaXNoZXIy MTk0ODM1