Vol. 26 No. 1 2024 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. 26 No. 1 2024 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, V.P. Larionov Institute of the Physical-Technical Problems of the North of the Siberian Branch of the RAS, Yakutsk; Alexander S. Yanyushkin, D.Sc. (Engineering), Professor, I.N. Ulianov Chuvash State University, Cheboksary
Vol. 26 No. 1 2024 5 CONTENTS OBRABOTKAMETALLOV TECHNOLOGY Kuts V.V., Oleshitsky A.V., Grechukhin A.N., Grigorov I.Y. Investigation of changes in geometrical parameters of GMAW surfaced specimens under the infl uence of longitudinal magnetic fi eld on electric arc....................................... 6 Saprykina N.А., Chebodaeva V.V., Saprykin A.А., Sharkeev Y.P., Ibragimov E.А., Guseva T.S. Optimization of selective laser melting modes of powder composition of the AlSiMg system................................................................. 22 Gubin D.S., Kisel’ A.G. Features of calculating the cutting temperature during high-speed milling of aluminum alloys without the use of cutting fl uid............................................................................................................................................. 38 EQUIPMENT. INSTRUMENTS Borisov M.A., Lobanov D.V., Zvorygin A.S., Skeeba V.Y. Adaptation of the CNC system of the machine to the conditions of combined processing...................................................................................................................................... 55 Nosenko V.A., Bagaiskov Y.S., Mirocedi A.E., GorbunovA.S. Elastic hones for polishing tooth profi les of heat-treated spur wheels for special applications..................................................................................................................................... 66 Podgornyj Y.I., Skeeba V.Y., Martynova T.G., Lobanov D.V., Martyushev N.V., Papko S.S., Rozhnov E.E., Yulusov I.S. Synthesis of the heddle drive mechanism....................................................................................................... 80 MATERIAL SCIENCE Ragazin A.A., Aryshenskii V.Y., Konovalov S.V., Aryshenskii E.V., Bakhtegareev I.D. Study of the eff ect of hafnium and erbium content on the formation of microstructure in aluminium alloy 1590 cast into a copper chill mold............................................................................................................................................................................ 99 Zorin I.A., Aryshenskii E.V., Drits A.M., Konovalov S.V. Study of evolution of microstructure and mechanical properties in aluminum alloy 1570 with the addition of 0.5 % hafnium........................................................................... 113 Karlina Y.I., Kononenko R.V., Ivantsivsky V.V., Popov M.A., Deryugin F.F., Byankin V.E. Relationship between microstructure and impact toughness of weld metals in pipe high-strength low-alloy steels (research review)..................... 129 Patil N.G., Saraf A.R., Kulkarni A.P Semi empirical modeling of cutting temperature and surface roughness in turning of engineering materials with TiAlN coated carbide tool................................................................................. 155 Sawant D., Bulakh R., Jatti V., Chinchanikar S., Mishra A., Sefene E.M. Investigation on the electrical discharge machining of cryogenic treated beryllium copper (BeCu) alloys........................................................................................ 175 Karlina A.I., Kondratiev V.V., Sysoev I.A., Kolosov A.D., Konstantinova M.V., Guseva E.A. Study of the eff ect of a combined modifi er from silicon production waste on the properties of gray cast iron................................................. 194 EDITORIALMATERIALS 212 FOUNDERS MATERIALS 223 CONTENTS
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 Study of the effect of hafnium and erbium content on the formation of microstructure in aluminium alloy 1590 cast into a copper chill mold Aleksandr Ragazin 1, a, *, Vladimir Aryshenskii 1, b, Sergey Konovalov 1, 2, c, Evgenii Aryshenskii 1, 2, c, Inzil Bakhtegareev 1, c 1 Samara National Research University named after S.P. Korolev, 34 Moskovskoe Shosse, Samara, 443086, Russian Federation 2 Siberian State Industrial University, 42 Kirova str., Novokuznetsk, 654007, Russian Federation a https://orcid.org/0000-0002-6762-7436, aleksander.ragazin@samara-metallurg.ru; b https://orcid.org/0000-0001-6869-4764, arysh54@mail.ru; c https://orcid.org/0000-0003-4809-8660, konovalov@sibsiu.ru; d https://orcid.org/0000-0003-3875-7749, arishenskiy_ev@sibsiu.ru; e https://orcid.org/0009-0004-3081-9049, bakhtegareev.id@ssau.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. 2024 vol. 26 no. 1 pp. 99–112 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2024-26.1-99-112 ART I CLE I NFO Article history: Received: 12 September 2023 Revised: 23 September 2023 Accepted: 16 November 2023 Available online: 15 March 2024 Keywords: Aluminum Lean doping with scandium Hafnium, Erbium Microstructure Intermetallic compounds Funding The study was supported by a grant of the Russian Science Foundation, project No. 22-19-00810, https://rscf.ru/ project/22-19-00810/ ABSTRACT Introduction. High-magnesium aluminum alloys are widely used in the automotive, building and aerospace industries due to its low specifi c gravity and high strength. The characteristics of such alloys can be improved by small additions of scandium and zirconium. However, scandium is very expensive, so in new generation alloys its amount is tended to be reduced. In the recently developed 1590 aluminum alloy, this was achieved by addition of erbium and hafnium. The objective of the paper is to study the eff ect of erbium and hafnium concentrations on the modifi cation of the cast structure in 1590 aluminum alloy at high solidifi cation rates. Research Methods. The paper investigates the microstructure, chemical composition and size of intermetallic compounds in specimens from ten alloy 1590 modifi cations with diff erent hafnium and erbium contents cast into a copper chill mold with a solidifi cation rate of 10 °C/sec. The grain structure was studied using an optical microscope. The chemical composition and size of the intermetallic phases were studied using a Tescan Vega 3 scanning electron microscope. Results and discussion. It is established that as the amount of hafnium and erbium increases, the cast structure is modifi ed. In general, grain refi nement with the addition of hafnium and erbium can be explained by a higher degree of supercooling between the solid and liquid phases. At a hafnium content of 0.16 %, the dendritic structure begins to transform into an equiaxed grain structure. This transformation can be explained by the appearance of primary intermetallic compounds of the Al3Sc type in the liquid phase. Such intermetallic compounds are identifi ed at a concentration of erbium and hafnium equal to 0.16 %. Moreover, in all alloys eutectic intermetallic compounds are identifi ed that contained manganese and iron and had no eff ect on the cast structure. Comparison with previously obtained results on the grain size of specimens cast into a steel mold shows that with higher solidifi cation rate, the structure modifi cation in 1590 alloy is getting less effi cient. This is explained by an increase in the concentration of transition elements in the solid solution, primarily scandium, necessary for the formation of primary intermetallic particles. For citation: Ragazin A.A., Aryshenskii V.Y., Konovalov S.V., Aryshenskii E.V., Bakhtegareev I.D. Study of the eff ect of hafnium and erbium content on the formation of microstructure in aluminium alloy 1590 cast into a copper chill mold. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2024, vol. 26, no. 1, pp. 99–112. DOI: 10.17212/1994-6309-2024-26.199-112. (In Russian). ______ * Corresponding author Ragazin Alexander A., Post-graduate Student Samara National Research University named after S.P. Korolev, 34 Moskovskoe Shosse, 443086, Samara, Russian Federation Tel.: +7 917 125-64-91, e-mail: aleksander.ragazin@samara-metallurg.ru Introduction Aluminum alloys, due to its low weight, high strength, and corrosion resistance, are widely used in modern industries. Magnesium is added to aluminum alloys to further enhance its properties. Aluminummagnesium alloys are in high demand by aviation and aerospace technologies due to its high strength. Scandium is added to improve the strength of this group of alloys, and a scandium concentration
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 of 0.5 % is ideal for refi ning the fi nished aluminum alloy structure. Scandium is an expensive metal, so attempts are continuously made to reduce its content by adding zirconium and hafnium. These elements stimulate the thermal stability of Al3Sc particles, and erbium precipitates as Al3Er nano-particles, increasing its total amount. The 1570 alloy is a conventional commercial high-magnesium aluminum alloy with combined scandium-zirconium additions. However, attempts are being made to further reduce the expensive scandium content in the alloys. For example, in the recently designed 1590 alloy, the scandium content varies in the range 0.06–0.16 %. Hafnium and erbium are added along with zirconium to reduce the scandium content in the alloy. The study aims to investigate the eff ect of erbium and hafnium concentrations on the modifi cation of the cast structure in 1590 aluminum alloy under fast crystallization conditions. The study will evaluate the grain structure formation when casting 1590 alloy into a copper chill mold and assess the eff ect of hafnium and erbium content on its size and type. It will also study the eff ect of erbium and hafnium on the formation of intermetallic particles, emerging during crystallization of 1590 alloy cast into a copper chill mold, and the relationship between intermetallic particles and grain structure size and type. Methods For the purpose of the study, ten melts were cast into a copper chill mold with diff erent chemical compositions as shown in Table 1. The melts contained Er and Hf in the range of 0.03–0.16 wt. % and 0.05–0.16 wt. %, respectively. These ranges are close to the minimal and maximal allowed concentrations of these elements in the 1590 alloy. The chemical compositions were previously analyzed in [21] as part of the study of 1590 alloy casting into a steel mold. Using the same compositions enables the comparison of the eff ects of crystallization rate on grain size in alloys with identical chemical compositions. Other elements in the melts corresponded to the chemical composition of the 1590 alloy, which was studied in [15, 16] from the perspective of heat treatment eff ect on microstructure and mechanical properties. Thus, this chemical composition allows the investigation of the eff ect of changes in Er and Hf concentrations on microstructure formation during casting and heat treatment. The charge stock used for experimental alloy design consisted of primary aluminum A85 grade, primary magnesium Mg90 grade, primary zinc TS1, and alloying compounds Al-Mn10, Al-Zr5, Al-Sc2, Al-Er5, and Al-Hf2. All materials were weighed using high-precision measurement devices before being charged into the furnace. The “MECHELECTRON-M VR4900” electronic scales, with a 5 g error, were used for materials weighing up to 15 kg, while the “MIDLENA 251” electronic scales were used for materials weighing up to 500 g, ensuring an accuracy level of plus/minus 0.1 g. The furnace was charged manually following the sequence below: 1. Primary aluminum was charged and melted fi rst. 2. Once the temperature reached 730 °C, slag was removed from the molten metal surface. 3. The molten metal was then heated to a temperature range of 770–790 °C. 4. Portions of 300 g of Al-Sc2, Al-Hf2, Al-Zr5, Al-Mn10 alloying compounds were sequentially introduced. 5. After each component was introduced, the molten metal was carefully stirred and soaked for 5 minutes. 6. After introducing all the calculated alloying components, the molten metal was cooled down to 740 °C. 7. Magnesium and zinc were then added to the molten metal. 8. The molten metal was stirred for 3 minutes using a titanium spoon. 9. The molten metal was reheated to 740°C. After casting, the chemical composition of all aluminum alloys was comprehensively studied using atomic emission spectroscopy with an ARL 3460 detector. The detector operates in the 0–10 keV energy range and has an energy resolution of 122 eV, which ensures accurate analysis. The analysis was carried out in accordance with the standards established by GOST 25086. Permissible concentration limits for key elements have been strictly established as follows: – Sc and Zn: 0.009 % – Hf, Zr, Er, Si, and Fe: 0.0053 %
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 – Mn: 0.018 % – Mg: 0.15 %. The chemical composition of all experimental melts was established experimentally and is presented in Table 1. The ingots were cast into a copper mold with a crystallization rate of 10 °C /s. Ta b l e 1 Chemical composition of the studied alloys Alloy Element weight fraction, % Al Si Fe Mn Mg Zn Zr Sc Er Hf 1590 basic base 0.03 0.06 0.42 5.54 0.19 0.1 0.14 – – 1590 Er0.03-Hf0.05 base 0.04 0.07 0.41 5.54 0.21 0.1 0.14 0.03 0.05 1590 Er0.03-Hf0.1 base 0.04 0.07 0.41 5.58 0.2 0.1 0.14 0.03 0.1 1590 Er0.03-Hf0.16 base 0.05 0.08 0.41 5.58 0.2 0.1 0.14 0.03 0.16 1590 Er0.1-Hf0.05 base 0.04 0.07 0.41 5.57 0.21 0.1 0.14 0.1 0.05 1590 Er0.1-Hf0.1 base 0.05 0.08 0.41 5.53 0.21 0.1 0.14 0.1 0.1 1590 Er0.1-Hf0.16 base 0.05 0.08 0.41 5.57 0.19 0.1 0.14 0.1 0.16 1590 Er0.16-Hf0.05 base 0.04 0.07 0.41 5.55 0.21 0.1 0.14 0.16 0.05 1590 Er0.16-Hf0.1 base 0.05 0.08 0.42 5.56 0.2 0.1 0.14 0.16 0.1 1590 Er0.16-Hf0.16 base 0.05 0.09 0.41 5.58 0.2 0.1 0.14 0.16 0.16 The grain structure of the specimens was analyzed using a complex optical microscope Carl Zeiss Axiovert-40 MAT. The average size of the grains was determined for each specimen using the secant method, which is described in GOST 21073.2. Furthermore, a Tescan Vega 3 scanning electron microscope was used to study the dimensions of intermetallic compounds in its cast state. The exact chemical composition of the structural elements in aluminum alloys 1590 Er0.03-Hf0.05, 1590 Er0.03-Hf0.16, 1590 Er0.16Hf0.05, and 1590 Er0.16-Hf0.16 were determined using energy-dispersive X-ray spectroscopy (EDS). The analysis was carried out using a Max 80T X-detector that operates in the energy range of 0–10 keV and has an energy resolution of 122 eV. The specimen preparation process involved several steps, including mechanical grinding, precision polishing, and electropolishing. Electropolishing was performed under controlled conditions, maintaining a temperature range of 85–110 °C and applying a voltage of 10–30 V. The electrolyte solution used for electropolishing comprised H3PO4 (500 ml), H2SO4 (300 ml), CrO3 (50 g), and H2O (50 ml). Results and discussion The analysis of the microstructure revealed that when cast into a copper chill mold, intermetallic compounds are formed by the process of eutectic reaction, and these compounds contain manganese and iron. The chemical composition of these compounds (as demonstrated in Table 2 and fi gures 1, 2) is similar to Al8 (FeMn), Al12 (FeMn), and MgSi2 [27]. It should be noted that to accurately determine the crystal structure of the phases, X-ray phase analysis is necessary. In this study, EDS analysis is conducted, which can determine the approximate chemical composition of intermetallic compounds and establish its correlation with the previously described phases that have similar compositions [28]. This study has successfully accomplished this. The alloys 1590 Er0.03-Hf0.05, 1590 Er0.03-Hf0.16 and 1590 Er0.16-Hf0.05, which were cast into a copper chill mold, contain manganese and iron and produce intermetallic compounds due to the eutectic
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 Al3(ScHfZr) а b c d Fig. 1. Chemical composition of large intermetallic particles in specimens cast into a copper chill mold: a) 1590 Er0.03-Hf0.05; b) 1590 Er0.03-Hf0.16; c) 1590 Er0.16-Hf0.05; d) 1590 Er0.16-Hf0.16 Ta b l e 2 Chemical composition of coarse intermetallic particles Mg Al Sc Hf Zr Mn Si Zn Fe Ti Er Al8(FeMn) 4.48 74.32 0.12 0.61 0.2 8.11 0.1 0.37 10.54 0 0.06 Al12(FeMn) 7.06 83.93 0.18 0.3 0.21 3.25 0.58 0.32 3.95 0.02 0.15 MgSi2 23.39 60.95 0.08 0 0.1 0.13 14.88 0.42 0 0.06 0 Al3ScHf 6.36 72.82 5.78 6.86 6.13 0.47 0.39 0.17 0.02 0.08 0.19 reaction. These compounds cannot modify the structure. However, particles of the Al3Sc-, Al3Hf-, and Al3Zr-type, modifying the cast structure, were not found in these alloys. The alloy 1590 Er0.16-Hf0.16 with a maximum content of hafnium and erbium at 0.16 % contains Al3Sc-type intermetallic compounds. The presence of zirconium and hafnium is explained by the fact that it can dissolve in the Al3Sc phase up to 35 % and 36 %, respectively. These compounds are primary intermetallic ones, i.e. are formed directly in
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 a b c d e f Fig. 2. Microstructure of the studied alloy specimens: a) 1590; b) 1590 Er0.03-Hf0.05; c) 1590 Er0.03-Hf0.1; d) 1590 Er0.03-Hf0.16; e) 1590 Er0.1-Hf0.05; f) 1590 Er0.1-Hf0.1; g) 1590 Er0.1-Hf0.16; h) 1590 Er0.16-Hf0.05; i) 1590 Er0.16-Hf0.1; j) 1590 Er0.16-Hf0.16 (see next page)
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 g h i j Fig. 2. The End the liquid phase before solid solution crystallization. It’s worth noting that some intermetallic compounds contain titanium, which is a result of using a titanium spoon during molten metal handling. The microstructure of specimens cast in a copper chill mold is illustrated in fi gure 2, while fi gure 3 shows the variation in grain size depending on the concentration of the element. It is worth noting that for comparison, fi gure 3 contains the results of the dependence of grain sizes on the concentration of chemical elements during casting into a steel mold, taken from [21]. The basic alloy, containing no erbium and hafnium, has a dendritic structure with an average grain size of 372 μm. It is worth noting that some grain sizes vary from 600 to 800 μm, while others stay within the range of 100–200 μm, as illustrated in fi gure 2, a. With the addition of 0.03 % Er and 0.05 % Hf to the basic alloy, the average grain size decreases to 181 μm. The number of grains with sizes of 600–800 μm decreases, while the number of grains with sizes of 100–200 μm increases, as shown in fi gure 2 b. With 0.03 % Er and 0.1 % Hf, the average grain size continues to decrease and reaches 175 μm. Most grains have sizes of 300–400 μm or 100 μm. At the same time, the fi rst 50 μm equiaxed grains appear, as seen in fi gure 2, c. With 0.03 % Er and 0.16 % Hf, the average grain size decreases to 86 μm, and almost all grains become equiaxed, as shown in fi gure 2, d. At 0.1 % Er and 0.05 % Hf, the average grain size reaches 113 μm, and two types of grains are observed: suffi ciently coarse 300–400 μm and fi ner 100–200 μm grains, maintaining overall dendritic structure (fi gure 2, e). In the alloy containing 0.1 % Er and 0.1 % Hf, the average grain size is 105 μm, and the overall pattern doesn’t diff er much from the previous case
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 Fig. 3. Dependence of grain size on the amount of alloying components (on specimens cast into a steel and copper chill molds) (fi gure 2, f). With the addition of 0.1 % Er and 0.16 % Hf, the grain sharply refi nes to 69 μm; most of the observed grains become equiaxed (although individual dendrites remain) (fi gure 2, g). With 0.16 % Er and 0.05 % Hf, the average grain size is 172 μm (fi gure 2, h). In general, in this case, the grain structure pattern corresponds to the pattern observed in 1590 Er0.03-Hf0.05 alloys. With 0.16 % Er and 0.1 % Hf, the grain size is 168 μm (fi gure 2, i), and the grain structure resembles the structure observed in 1590 Er0.03-Hf0.05 and 1590 Er0.16-Hf0.05 alloys. The alloy 1590 Er0.16-Hf0.16 demonstrates a notable average grain size drop to 64 μm, and the structure acquires the equiaxed shape, as shown in fi gure 2, j. The analysis of the results leads to the conclusion that hafnium primarily presents the primary grain modifi er. For instance, when alloy contains 0.05 %, 0.1 %, and 0.16 % Hf, increasing the Er content from 0.03 % to 0.16 % reduces the grain size by only 191, 76, and 36 μm, respectively. At the same time, Hf content growth from 0.05 % to 0.16 % enables decreasing the average grain size from 181 to 64 μm. However, most importantly, hafnium transforms the grain structure into an equiaxed type. This is the eff ect of Al3Sc intermetallic compounds, containing both zirconium and hafnium, which are capable of modifying the as-cast structure (fi g. 1d). The following factors explain its capability to refi ne grain: fi rstly, unlike other detected intermetallic compounds, it is formed in the liquid phase prior to aluminum solid solution crystallization; secondly, it has crystalline lattice parameters close to aluminum matrix parameters. This ultimately gives it the opportunity to act as nuclei of new grains consisting of an aluminum solid solution. Note that such intermetallic compounds were detected only in alloy 1590 Er0.16-Hf0.16, due to its reasonably small size (about 1 μm). Therefore, it is rather diffi cult to detect and identify it using SEM. Thus, only indirect evidence of its presence is used, i.e., dendritic structure becomes equiaxed. It should also be noted that grain refi nement without dendritic structure conversion to equiaxed structure occurs as hafnium concentration increases from 0.05 to 0.1 % and erbium concentration increases from 0.03 to 0.16 %. This can be explained by the fact that an increase in the concentration of transition elements, especially hafnium, can also promote grain refi nement due to increased supercooling between the liquid and solid phase nuclei. Figure 3 demonstrates that when casting into a steel chill mold, the grain size is half as large as when casting into a copper chill mold. This is explained by the fact that with an increase in the crystallization rate,
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 transition metals do not have time to precipitate in the form of primary intermetallic compounds and remain in a supersaturated solid solution, which is confi rmed in [31]. It shows that Al3Zr-type primary intermetallic compounds are not formed at a higher crystallization rate of aluminum alloy with zirconium addition. At the same time, zirconium itself remains in a supersaturated solid solution. In our case, the same eff ect is identifi ed in the alloys containing hafnium and erbium, except for 1590 Er0.16-Hf0.16, where close to Al3(Zr,Sc,Hf) primary intermetallic compounds [21]. In order to understand the phenomenon of transition elements migrating to the supersaturated solid solution at high casting rates, let us take the example of the aluminum-scandium phase diagram illustrated in fi gure 4. The fi gure shows the eutectic interaction in the aluminum-rich zone, which is identifi ed by point E. At a temperature of 655 °C and a scandium content of 0.55 wt % scandium, the equilibrium state Zh↔ ((Al) + Al3Sc) is achieved. When the cooling rate of the aluminum-based alloy increases to 10 °С/s, a marked shift in the eutectic interaction temperature from equilibrium conditions becomes apparent. The Sc content increases to 0.8 wt%, which enables the formation of primary intermetallic compounds, identifi ed as E’ in the diagram. Thus, with an increased rate of crystallization in alloys where a dendritic structure is observed, the concentration of scandium, zirconium, hafnium and erbium required for the formation of primary intermetallic compounds increases, so the content of these transition elements for the appearance of such particles becomes insuffi cient. Conclusions An increase in the content of erbium and, mainly, hafnium helps to refi ne the grain structure. However, only when the content of hafnium reaches 0.16 %, the dendritic structure is replaced by an equiaxed one. This is because the refi nement process begins due to supercooling between the nuclei of solid and liquid phases. When the hafnium content reaches 0.16 %, primary intermetallic compounds emerge in the liquid phase, thus facilitating refi nement and causing a modifi cation of the as-cast structure. Intermetallic compounds, which have no eff ect on the modifi cation of the as-cast structure, are identifi ed in all alloys close to Al8(Fe,Mn), Al12(Fe,Mn), and MgSi2 eutectic origin. Al3Sc-type primary intermetallic compounds were found only in the 1590 Er0.16-Hf0.16, and its presence in other alloys containing 0.16 % hafnium can be indicated only by indirect indicators, such as as-cast structure refi nement. The absence of these intermetallic compound traces can be explained by its relatively small sizes in such alloys, making its identifi cation and detection diffi cult using scanning microscopy. An increase in the crystallization rate of the 1590 alloy leads to grain size growth at any content of erbium and hafnium. This is mainly due to the fact that an increase in the casting rate leads to an increase in the concentration of transition elements required for the formation of primary intermetallic compounds that act as grain modifi ers in the liquid phase. Fig. 4. Aluminum-scandium phase diagram [32] References 1. Alattar A.L.A., Bazhin V.Yu. Kompozitsionnye materialy Al-Cu-B4C dlya polucheniya vysokoprochnykh zagotovok [Al-Cu-B4C composite materials for production of high-strength workpieces]. Metallurg = Metallurgist, 2020, no. 6, pp. 65–70. (In Russian).
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 2. Deev V.B., Ri E.H., Prusov E.S., Ermakov M.A., Goncharov A.V. Grain refi nement of casting aluminum alloys of the Al–Mg–Si system by processing the liquid phase using nanosecond electromagnetic pulses. Russian Journal of Non-Ferrous Metals, 2021, vol. 62 (5), pp. 522–530. DOI: 10.3103/S1067821221050023. 3. Shurkin P.K., Belov N.A., Musin A.F., Aksenov A.A. Novel high-strength casting Al−Zn−Mg−Ca−Fe aluminum alloy without heat treatment. Russian Journal of Non-Ferrous Metals, 2020, vol. 61 (2), pp. 179–187. DOI: 10.3103/S1067821220020121. 4. Musfi rah A.H., Jaharah A.G. Magnesium and aluminum alloys in automotive industry. Journal of Applied Sciences Research, 2012, vol. 8 (9), pp. 4865–4875. 5. Benedyk J.C. Aluminum alloys for lightweight automotive structures. Materials, design and manufacturing for lightweight vehicles. Woodhead Publishing, 2010, ch. 3, pp. 79–113. DOI: 10.1533/9781845697822.1.79. 6. Petrov A.P., Golovkin P.A. Rezhimy goryachei deformatsii i tekhnologicheskaya plastichnost’ splavov sistem Al–Mg i Al–Mg–Sc [Modes of hot deformation and technological plasticity of alloys of Al-Mg and Al-Mg-Sc systems]. Perspektivnye tekhnologii legkikh i spetsial’nykh splavov [Promising technologies of light and special alloys]. Moscow, Fizmatlit Publ., 2006, pp. 213–221. ISBN 5-9221-0716-Х. 7. Rana R.S., Purohit R., Das S. Reviews on the infl uences of alloying elements on the microstructure and mechanical properties of aluminum alloys and aluminum alloy composites. International Journal of Scientifi c and Research Publications, 2012, vol. 2 (6), pp. 1–7. 8. Sanders R.E., Baumann S.F., Stumpf H.C. Wrought non-heat treatable aluminum alloys. Treatise in Materials Science & Technology. Academic Press, 1989, vol. 31, pp. 65–105. DOI: 10.1016/B978-0-12-341831-9.50008-5. 9. NormanA.F., Prangnell P.B., McEwen R.S. The solidifi cation behaviour of dilute aluminium–scandium alloys. Acta Materialia, 1998, vol. 46 (16), pp. 5715–5732. DOI: 10.1016/S1359-6454(98)00257-2. 10. Zakharov V.V. Eff ect of scandium on the structure and properties of aluminum alloys. Metal Science and Heat Treatment, 2003, vol. 45 (7–8), pp. 246–253. DOI: 10.1023/A:1027368032062. 11. Davydov V.G., Elagin V.I., Zakharov V.V., Rostoval D. Alloying aluminum alloys with scandium and zirconium additives. Metal Science and Heat Treatment, 1996, vol. 38 (8), pp. 347–352. DOI: 10.1007/BF01395323. 12. Yin Z., Pan Q., Zhang Y., Jiang F. Eff ect of minor Sc and Zr on the microstructure and mechanical properties of Al–Mg based alloys. Materials Science and Engineering: A, 2000, vol. 280 (1), pp. 151–155. DOI: 10.1016/ S0921-5093(99)00682-6. 13. Bronz A.V., Еfremov V.I., Plotnikov A.D., Chernyavsky A.G. Splav 1570S – material dlya germetichnykh konstruktsii perspektivnykh mnogorazovykh izdelii RKK «Energiya» [Alloy 1570C – material for pressurized structures of advanced reusable vehicles of RSC Energia]. Kosmicheskaya tekhnika i tekhnologii = Space Engineering and Technology, 2014, no. 4 (7), pp. 62–67. 14. Avtokratova E.V. Perspektivnyi Al-Mg-Sc splav dlya samoletostroeniya [Promising Al-Mg-Sc alloy for aircraft construction]. Vestnik Ufi mskogo gosudarstvennogo aviatsionnogo tekhnicheskogo universiteta. = Vestnik UGATU, 2007, vol. 9 (1), pp. 182–183. 15. Aryshensky E.V., Aryshensky V.Yu., Drits А.М., Grechnikov F.V., Ragazin А.А. Vliyanie rezhimov termicheskoi obrabotki na mekhanicheskie svoistva alyuminievykh splavov 1570, 1580 i 1590 [Thermal treatment eff ect on the mechanical properties of 1570, 1580 and 1590 aluminum alloys]. Vestnik Samarskogo universiteta. Aerokosmicheskaya tekhnika, tekhnologii i mashinostroenie = Vestnik of Samara University. Aerospace and Mechanical Engineering, 2022, vol. 21 (4), pp. 76–87. DOI: 10.18287/2541-7533-2022-21-4-76-87. 16. Ragazin A.A., Aryshenskii E.V., Aryshenskii V.Yu., Drits A.M., Konovalov S.V. Issledovanie raspada peresyshchennogo tverdogo rastvora v novykh vysokomagnievykh splavakh, ekonomnolegirovannykh malymi skandievymi dobavkami [Studies of supersaturated solid solution decomposition in new magnesium rich aluminum alloys with minor scandium additions]. Fundamental’nye problemy sovremennogo materialovedeniya = Basic Problems of Material Science, 2022, vol. 19 (4), pp. 491–500. DOI: 10.25712/ASTU.1811-1416.2022.04.008. 17. Drits A.M., Aryshenskii V.Yu., Aryshenskii E.V., Zaharov V.V. Svarivaemyi termicheski ne uprochnyaemyi splav na osnove sistemy Al-Mg [Welded thermally non-hardened alloy based on Al-Mg system]. Patent RF, no. 2726520 C1, 2020. 18. Teleshov V.V. Fundamental’naya zakonomernost’ izmeneniya struktury pri kristallizatsii alyuminievykh splavov s raznoi skorost’yu okhlazhdeniya [Fundamental relationship of aluminum alloy structure modifi cation during solidifi cation with diff erent cooling rates]. Tekhnologiya legkikh splavov = Technology of Light Alloys, 2015, no. 2, pp. 13–18. 19. HallemH., LefebvreW., Forbord B., Danoix F., MarthinsenK. The formation ofAl3(ScxZryHf1−x−y)-dispersoids in aluminium alloys. Materials Science and Engineering: A, 2006, vol. 421 (1–2), pp. 154–160. DOI: 10.1016/j. msea.2005.11.063.
OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 1 2024 20. Hallem H., Forbord B., Marthinsen K. Investigation of Al-Fe-Si alloys with additions of Hf, Sc and Zr. Materials Forum, 2004, vol. 28, pp. 825–831. 21. Aryshensky V.Yu., Aryshensky E.V., Ragazin A.A., Bakhtegareev I.D., Konovalov S.V. [Investigation of the infl uence of hafnium and erbium on the microstructure of a casting billet in a high-magnesium aluminum alloy with economically alloyed scandium]. Metallurgiya: tekhnologii, innovatsii, kachestvo «Metallurgiya-2022» [Metallurgy: technologies, innovations, quality]. Proceedings of the XXIII International scientifi c and practical conference. Novokuznetsk, Siberian State Industrial University Publ., 2022, pt. 1, pp. 156–161. (In Russian). 22. Yao W.J., Wang N., Wei B. Containerless rapid solidifi cation of highly undercooled Co-Si eutectic alloys. Materials Science and Engineering: A, 2003, vol. 344 (1–2), pp. 10–19. DOI: 10.1016/S0921-5093(01)01895-0. 23. Cai J., Ma G.C., Liu Z., Zhang H.F., Hu Z.Q. Infl uence of rapid solidifi cation on the microstructure ofAZ91HP alloy. Journal of Alloys and Compounds, 2006, vol. 422 (1–2), pp. 92–96. DOI: 10.1016/j.jallcom.2005.11.054. 24. Wang F., Qiu D., Liu Z., Taylor J.A., Easton M.A., Zhang M. The grain refi nement mechanism of cast aluminium by zirconium. Acta Materialia, 2013, vol. 61 (15), pp. 5636–5645. DOI: 10.1016/j.actamat.2013.05.044. 25. Li H., Li D., Zhu Z., Chen B., Chen X., Yang Ch., Zhang H., Kang W. Grain refi nement mechanism of ascast aluminum by hafnium. Transactions of Nonferrous Metals Society of China, 2016, vol. 26 (12), pp. 3059–3069. DOI: 10.1016/S1003-6326(16)64438-2. 26. Zakharov V.V. Osobennosti kristallizatsii alyuminievykh splavov, legirovannykh skandiem [Special features of crystallization of scandium-alloyed aluminum alloys]. Metallovedenie i termicheskaya obrabotka metallov = Metal Science and Heat Treatment, 2011, no. 9, pp. 12–18. (In Russian). 27. Warmuzek M., Ratuszek W., Sęk-Sas G. Chemical inhomogeneity of intermetallic phases precipitates formed during solidifi cation of Al-Si alloys. Materials Characterization, 2005, vol. 54 (1), pp. 31–40. DOI: 10.1016/j. matchar.2004.10.001. 28. Engler O., Kuhnke K., Hasenclever J. Development of intermetallic particles during solidifi cation and homogenization of two AA 5xxx series Al-Mg alloys with diff erent Mg contents. Journal of Alloys and Compounds, 2017, vol. 728, pp. 669–681. DOI: 10.1016/j.jallcom.2017.09.060. 29. Röyset J., Ryum N. Scandium in aluminium alloys. International Materials Reviews, 2005, vol. 50 (1), pp. 19–44. DOI: 10.1179/174328005X14311. 30. Rokhlin L.L., Bochvar N.R., Boselli J., Dobatkina T.V. Investigation of the phase relations in the Al-rich alloys of the Al–Sc–Hf system in solid state. Journal of Phase Equilibria and Diff usion, 2010, vol. 31, pp. 327–332. DOI: 10.1007/s11669-010-9710-z. 31. Belotserkovets V.V. Zakonomernosti polucheniya nedendritnoi struktury v alyuminievykh splavakh s tsirkoniem [Mechanisms of a nondendritic structure development in zirconium-bearing aluminium alloys]. Tekhnologiya legkikh splavov = Technology of Light Alloys, 2013, no. 4, pp. 160–168. 32. Kosov Ya.I. Perspektivnye kompozitsii alyuminievykh splavov i ligatur [Advanced composition of aluminum alloys and master alloys]. Mezhdunarodnyi nauchno-issledovatel’skii zhurnal = International Research Journal, 2016, no. 11-4 (53), pp. 73–77. (In Russian). 33. Lyakishev N.P., ed. Diagrammy sostoyaniya dvoinykh metallicheskikh sistem. V 3 t. T. 1 [Handbook of binary metallic systems. In 3 vols. Vol. 1]. Moscow, Mashinostroenie Publ., 1996. 992 p. ISBN 5-217-02688-X. Confl icts of Interest The authors declare no confl ict of interest. © 2024 The Authors. Published by Novosibirsk State Technical University. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0).
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