Obrabotka Metallov / Metal Working and Material ScienceObrabotka Metallov / Metal Working and Material ScienceОбработка металлов (технология • оборудование • инструменты)1994-63092541-819XНовосибирский государственный технический университет46266710.17212/1994-6309-2026-28.3-83-111SSISCRTECHNOLOGYТЕХНОЛОГИЯResearch ArticleInfluence of high-frequency electromagnetic field-assisted TIG surface modification on microstructural evolution, elemental redistribution and hardness of EN-GJV-400 compacted graphite ironВлияние высокочастотного электромагнитного поля на эволюцию микроструктуры, перераспределение легирующих элементов и твердость поверхностных слоев компактного графитового чугуна EN-GJV-400, полученных TIG-модификациейhttps://orcid.org/0009-0006-9378-9865ШирзадовФархад МагамедShirzadovFarhad Mahammad
Azerbaijan

доцент

Associate Professor

farhad.shirzadov@aztu.edu.azАзербайджанский технический университетAzerbaijan Technical Universityruen283ТОМ 28, №3 (2026)VOL 28, NO3 (2026)8311107072026Copyright ©; 2026, Ширзадов Ф.М.Copyright ©; 2026, Shirzadov F.M.2026Ширзадов Ф.М.Shirzadov F.M.https://creativecommons.org/licenses/by/4.0https://journals.rcsi.science/1994-6309/article/view/462667

Introduction. Compacted graphite iron (EN-GJV-400) is widely used for highly loaded automotive and engineering components due to its favourable combination of strength, thermal conductivity, damping capacity and castability. However, the relatively moderate hardness and wear resistance of its surface region may limit its application under severe contact conditions. High-frequency electromagnetic field (HFEMF)-assisted treatment represents a potential approach for modifying solidification conditions and improving structural uniformity during surface engineering. Nevertheless, the influence of HFEMF-assisted TIG treatment on the microstructural evolution, elemental redistribution and hardness response of compacted graphite iron remains insufficiently understood. Materials and methods. In this study, conventional and HFEMF-assisted TIG surface modification of EN-GJV-400 compacted graphite iron was investigated. The experimental program included TIG remelting, TIG surface alloying using Ni78Si8B14 and CuSn-4 foils, and TIG hardfacing using UTP A DUR 600 chromium-containing filler wire, performed with and without electromagnetic assistance. A high-frequency electromagnetic field with a frequency of 200 kHz was applied during treatment. The modified surface layers were characterized using optical microscopy, scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM/EDS) and Vickers microhardness measurements. Results and discussion. The obtained results indicate that HFEMF-assisted processing influences the structural development of TIG-modified layers by affecting the conditions of heat and mass transfer during melting and solidification. The influence of HFEMF was evaluated indirectly through surface morphology, microstructural characteristics, elemental distribution and hardness response. Conventional TIG remelting increased the surface hardness of EN-GJV-400 from approximately 375 HV0.1 to 765 HV0.1 due to graphite dissolution, carbon redistribution and formation of ledeburitic structures containing cementite-rich constituents. HFEMF-assisted remelting produced a comparable hardness level of approximately 760 HV0.1, indicating that electromagnetic assistance does not act as an independent strengthening mechanism but mainly contributes to structural homogenization. Ni78BSi8B14 alloying resulted in hardened transformation products together with ledeburitic and carbide-containing constituents, while HFEMF primarily improved the uniformity of alloy-element distribution. For UTP A DUR 600 hardfacing, HFEMF-assisted treatment increased the average hardness from approximately 771 HV0.1 to 800 HV0.1, which is attributed to improved redistribution and more uniform formation of chromium-containing hard phases. Conclusion. The results demonstrate that HFEMF-assisted TIG treatment provides an additional process-control parameter for surface modification of EN-GJV-400 compacted graphite iron. The effectiveness of electromagnetic assistance depends on the chemical composition of the modified layer and the dominant strengthening mechanism. HFEMF should therefore be considered primarily as a method for improving structural uniformity, elemental redistribution and phase distribution rather than as a universal hardness-enhancement technique. Further studies involving direct molten-pool observation and numerical modelling are required to quantitatively establish the relationship between electromagnetic parameters and melt-pool behaviour.

Введение. Компактный графитизированный чугун EN-GJV-400 широко применяется для изготовления высоконагруженных автомобильных и машиностроительных компонентов благодаря сочетанию прочности, теплопроводности, демпфирующей способности и технологичности. Однако ограниченные значения твердости и износостойкости поверхностного слоя снижают его эксплуатационные характеристики в условиях интенсивного контактного нагружения. Применение высокочастотного электромагнитного поля (ВЧЭМП) является перспективным методом управления процессами тепло- и массопереноса при поверхностной обработке, однако его влияние на формирование структуры EN-GJV-400 изучено недостаточно. Методы исследования. Проведено сравнительное исследование традиционной и ВЧЭМ-ассистированной TIG-модификации поверхности EN-GJV-400. Исследованы TIG-оплавление, поверхностное легирование фольгами Ni78Si8B14 и CuSn-4, а также наплавка проволокой UTP A DUR 600 с применением электромагнитного поля частотой 200 кГц. Формирование поверхностных слоев исследовали методами оптической и сканирующей электронной микроскопии с EDS-анализом, а также измерением микротвердости по Виккерсу. Результаты и обсуждение. Установлено, что ВЧЭМП изменяет условия тепло- и массопереноса в расплавленной зоне, способствуя повышению структурной однородности и равномерности распределения легирующих элементов. TIG-оплавление повысило твердость поверхности с 375 до 765 HV0.1 за счет растворения графита, перераспределения углерода и формирования ледебуритных структур с цементитсодержащими фазами. ВЧЭМ-оплавление обеспечило сопоставимую твердость (~760 HV0.1), но с более однородной структурой. Для наплавки UTP A DUR 600 применение ВЧЭМП повысило твердость с 771 до 800 HV0.1 вследствие более равномерного распределения хромсодержащих твердых фаз. Заключение. ВЧЭМ-ассистированная TIG-модификация EN-GJV-400 является эффективным инструментом управления формированием поверхностных слоев. Основное влияние ВЧЭМП заключается не в прямом упрочнении, а в регулировании процессов перераспределения элементов, формирования фаз и в повышении структурной однородности модифицированных слоев.

EN-GJV-400TIG-оплавление поверхностиВысокочастотное электромагнитное полеЗакономерности затвердеванияИнженерия поверхности.EN-GJV-400TIG remeltingHigh-frequency electromagnetic fieldSolidification behaviorSurface engineering

Благодарности

Автор выражает признательность за то, что часть экспериментальных исследований была выполнена в Техническом университете Берлина (Германия) в рамках научного сотрудничества и исследовательской деятельности, связанной с технологиями поверхностной инженерии. Текущая институциональная принадлежность автора – Азербайджанский технический университет, где исследовательская работа была продолжена, развита и подготовлена к публикации. Автор выражает благодарность за предоставленные экспериментальные возможности и научную поддержку, оказанные во время исследовательского пребывания в Техническом университете Берлина.

Acknowledgments

The author acknowledges that part of the experimental investigations was conducted at the Technical University of Berlin (Germany) within the framework of scientific cooperation and research activities related to surface engineering technologies. The authors' current institutional affiliation is Azerbaijan Technical University, where the research work was further developed and prepared for publication. The experimental facilities and scientific support provided during the research stay at TU Berlin are gratefully acknowledged.

König M. Literature review of microstructure formation in compacted graphite iron. International Journal of Cast Metals Research, 2010, vol. 23 (3), pp. 185–192. DOI: 10.1179/136404609X12535244328378.König M. Literature review of microstructure formation in compacted graphite iron // International Journal of Cast Metals Research. – 2010. – Vol. 23 (3). – P. 185–192. – DOI: 10.1179/136404609X12535244328378.Patel M., Dave K. An insight of compacted graphite iron (CGI) characteristics and its production: A review. Recent Advances in Manufacturing Processes and Systems. Singapore, Springer, 2022, pp. 131–148. ISBN 978-981-16-7787-8. DOI: 10.1007/978-981-16-7787-8_10.Patel M., Dave K. An insight of compacted graphite iron (CGI) characteristics and its production: A review // Recent Advances in Manufacturing Processes and Systems. – Singapore: Springer, 2022. – P. 131–148. – ISBN 978-981-16-7787-8. – DOI: 10.1007/978-981-16-7787-8_10.Dawson S., Guesser W.L. Castability, product design and production of compacted graphite irons. ASM Handbook. Vol. 1A: Cast Iron Science and Technology. Materials Park, Ohio, ASM International, 2017. ISBN 978-1-62708-168-3. DOI: 10.31399/asm.hb.v01a.a0006328.Dawson S., Guesser W.L. Castability, product design and production of compacted graphite irons // ASM Handbook. Vol. 1A: Cast Iron Science and Technology. – Materials Park, Ohio: ASM International, 2017. – ISBN 978-1-62708-168-3. – DOI: 10.31399/asm.hb.v01a.a0006328.Bukhari S.M.A., Husnain N., Siddiqui F.A., Anwar M.T., Khosa A.A., Imran M., Qureshi T.H., Ahmad R. Effect of laser surface remelting on microstructure, mechanical properties and tribological properties of metals and alloys: A review. Optics and Laser Technology, 2023, vol. 165, p. 109588. DOI: 10.1016/j.optlastec.2023.109588.Effect of laser surface remelting on microstructure, mechanical properties and tribological properties of metals and alloys: A review / S.M.A. Bukhari, N. Husnain, F.A. Siddiqui, M.T. Anwar, A.A. Khosa, M. Imran, T.H. Qureshi, R. Ahmad // Optics and Laser Technology. – 2023. – Vol. 165. – P. 109588. – DOI: 10.1016/j.optlastec.2023.109588.Wollmann D., Pintaude G. Tribological performance of high-strength cast iron in lubricated contact containing carbon black. Wear, 2021, vol. 496–497, p. 203743. DOI: 10.1016/j.wear.2021.203743.Wollmann D., Pintaude G. Tribological performance of high-strength cast iron in lubricated contact containing carbon black // Wear. – 2021. – Vol. 496–497. – P. 203743. – DOI: 10.1016/j.wear.2021.203743.Gregorutti R.W., Grau J.E. Mechanical properties of compacted graphite cast iron with different microstructures. International Journal of Cast Metals Research, 2014, vol. 27 (5), pp. 275–281. DOI: 10.1179/1743133614Y.0000000118.Gregorutti R.W., Grau J.E. Mechanical properties of compacted graphite cast iron with different microstructures // International Journal of Cast Metals Research. – 2014. – Vol. 27 (5). – P. 275–281. – DOI: 10.1179/1743133614Y.0000000118.Chen Y., Pang J.C., Li S.X., Zou C.L., Zhang Z.F. Damage mechanism and fatigue strength prediction of compacted graphite iron with different microstructures. International Journal of Fatigue, 2022, vol. 164, p. 107126. DOI: 10.1016/j.ijfatigue.2022.107126.Damage mechanism and fatigue strength prediction of compacted graphite iron with different microstructures / Y. Chen, J.C. Pang, S.X. Li, C.L. Zou, Z.F. Zhang // International Journal of Fatigue. – 2022. – Vol. 164. – P. 107126. – DOI: 10.1016/j.ijfatigue.2022.107126.Ray J., Acharyya S.K., Misra D. Surface modification of engineering materials using TIG cladding technique: A review. Recent Advances in Manufacturing Engineering. Singapore, Springer, 2025, pp. 173–183. ISBN 978-981-96-9767-0. DOI: 10.1007/978-981-96-9768-7_14.Ray J., Acharyya S.K., Misra D. Surface modification of engineering materials using TIG cladding technique: A review // Recent Advances in Manufacturing Engineering. – Singapore: Springer, 2025. – P. 173–183. – ISBN 978-981-96-9767-0. – DOI: 10.1007/978-981-96-9768-7_14.Mitelea I., Bordeaşu I., Riemschneider E., Uţu I.D., Crăciunescu C.M. Cavitation erosion improvement following TIG surface-remelting of gray cast iron. Wear, 2022, vol. 496–497, p. 204282. DOI: 10.1016/j.wear.2022.204282.Cavitation erosion improvement following TIG surface-remelting of gray cast iron / I. Mitelea, I. Bordeasu, E. Riemschneider, I.D. Utu, C.M. Craciunescu // Wear. – 2022. – Vol. 496–497. – P. 204282. – DOI: 10.1016/j.wear.2022.204282.Sun B., Cheng J., Cai Z., Zhao H., Zhang Z., Qu H., Zhang Q., Hong S., Liang X. Formation and wear property of broad-beam laser clad Fe-based coatings. Surface and Coatings Technology, 2021, vol. 405, p. 126598. DOI: 10.1016/j.surfcoat.2020.126598.Formation and wear property of broad-beam laser clad Fe-based coatings / B. Sun, J. Cheng, Z. Cai, H. Zhao, Z. Zhang, H. Qu, Q. Zhang, S. Hong, X. Liang // Surface and Coatings Technology. – 2021. – Vol. 405. – P. 126598. – DOI: 10.1016/j.surfcoat.2020.126598.Rakhmonov J.U., Weiss D., Dunand D.C. Comparing evolution of precipitates and strength upon aging of cast and laser-remelted Al–8Ce–0.2Sc–0.1Zr alloys. Materials Science and Engineering: A, 2022, vol. 840, p. 142990. DOI: 10.1016/j.msea.2022.142990.Rakhmonov J.U., Weiss D., Dunand D.C. Comparing evolution of precipitates and strength upon aging of cast and laser-remelted Al–8Ce–0.2Sc–0.1Zr alloys // Materials Science and Engineering: A. – 2022. – Vol. 840. – P. 142990. – DOI: 10.1016/j.msea.2022.142990.Song Y., Wu W., Yu Y., Hua L. Effects of electric and magnetic treatments on microstructures of solid metals: A review. Chinese Journal of Mechanical Engineering, 2023, vol. 36, p. 139. DOI: 10.1186/s10033-023-00961-y.Effects of electric and magnetic treatments on microstructures of solid metals: A review / Y. Song, W. Wu, Y. Yu, L. Hua // Chinese Journal of Mechanical Engineering. – 2023. – Vol. 36. – P. 139. – DOI: 10.1186/s10033-023-00961-y.Lim Y.C., Yu X., Cho J.H., Sosa J., Farson D.F., Babu S.S., McCracken S., Flesner B. Effect of magnetic stirring on grain structure refinement. Part 1: Autogenous nickel alloy welds. Science and Technology of Welding and Joining, 2010, vol. 15 (7), pp. 583–589. DOI: 10.1179/136217110X12720264008277.Effect of magnetic stirring on grain structure refinement. Part 1: Autogenous nickel alloy welds / Y.C. Lim, X. Yu, J.H. Cho, J. Sosa, D.F. Farson, S.S. Babu, S. McCracken, B. Flesner // Science and Technology of Welding and Joining. – 2010. – Vol. 15 (7). – P. 583–589. – DOI: 10.1179/136217110X12720264008277.Tan C., Chen B., Liu F., Zhang X., Chen S., Song X. Numerical study on weld pool behaviors and keyhole dynamics in magnetic-field-assisted laser-arc hybrid welding of aluminum alloy. Journal of Materials Research and Technology, 2023, vol. 26, pp. 6446–6461. DOI: 10.1016/j.jmrt.2023.09.030.Numerical study on weld pool behaviors and keyhole dynamics in magnetic-field-assisted laser-arc hybrid welding of aluminum alloy / C. Tan, Y. Dong, H. Sun, F. Liu, X. Han, Q. Dong, B. Chen, X. Song // Journal of Materials Research and Technology. – 2023. – Vol. 26. – P. 6446–6461. – DOI: 10.1016/j.jmrt.2023.09.030.Xu W., Shi Y., Cui Y., Liang Z. Effects of magnetic fields in arc welding, laser welding and resistance spot welding: A review. Advanced Engineering Materials, 2022, p. 2200682. DOI: 10.1002/adem.202200682.Effects of magnetic fields in arc welding, laser welding and resistance spot welding: A review / W. Xu, Y. Shi, Y. Cui, Z. Liang // Advanced Engineering Materials. – 2022. – P. 2200682. – DOI: 10.1002/adem.202200682.Bai Q., Zhang K., Tian Y., Zhang J., Liu T., Liu Y., Wang B. Effect of Lorentz force distribution on solidified microstructure and segregation of magnesium alloys under pulsed electromagnetic field. Journal of Alloys and Compounds, 2025, vol. 1039, p. 183014. DOI: 10.1016/j.jallcom.2025.183014.Effect of Lorentz force distribution on solidified microstructure and segregation of magnesium alloys under pulsed electromagnetic field / Q. Bai, T. Liu, Y. Tian, K. Zhang, Y. Liu, J. Zhang, B. Wang // Journal of Alloys and Compounds. – 2025. – Vol. 1039. – P. 183014. – DOI: 10.1016/j.jallcom.2025.183014.Meng X., Bachmann M., Artinov A., Rethmeier M. Experimental and numerical assessment of weld pool behavior and final microstructure in wire feed laser beam welding with electromagnetic stirring. Journal of Manufacturing Processes, 2019, vol. 45, pp. 408–418. DOI: 10.1016/j.jmapro.2019.07.021.Experimental and numerical assessment of weld pool behavior and final microstructure in wire feed laser beam welding with electromagnetic stirring / X. Meng, M. Bachmann, A. Artinov, M. Rethmeier // Journal of Manufacturing Processes. – 2019. – Vol. 45. – P. 408–418. – DOI: 10.1016/j.jmapro.2019.07.021.Zhang Z., Xu X., Ge P., Li K. Numerical modeling of electromagnetic field influences on fluid thermodynamic behavior and grain growth during solidification of 316L stainless steel laser-welded plates. Metals, 2025, vol. 15 (6), p. 609. DOI: 10.3390/met15060609.Numerical modeling of electromagnetic field influences on fluid thermodynamic behavior and grain growth during solidification of 316L stainless steel laser-welded plates / Z. Zhang, X. Xu, P. Ge, K. Li // Metals. – 2025. – Vol. 15 (6). – P. 609. – DOI: 10.3390/met15060609.Meng X., Bachmann M., Artinov A., Rethmeier M. The influence of magnetic field orientation on metal mixing in electromagnetic stirring enhanced wire feed laser beam welding. Journal of Materials Processing Technology, 2021, vol. 294, p. 117135. DOI: 10.1016/j.jmatprotec.2021.117135.The influence of magnetic field orientation on metal mixing in electromagnetic stirring enhanced wire feed laser beam welding / X. Meng, M. Bachmann, A. Artinov, M. Rethmeier // Journal of Materials Processing Technology. – 2021. – Vol. 294. – P. 117135. – DOI: 10.1016/j.jmatprotec.2021.117135.Balasubramani N., Venezuela J., StJohn D., Wang G., Dargusch M.A. A review of the origin of equiaxed grains during solidification under mechanical stirring, vibration, electromagnetic, electric-current and ultrasonic treatments. Journal of Materials Science & Technology, 2023, vol. 144, pp. 243–265. DOI: 10.1016/j.jmst.2022.09.067.A review of the origin of equiaxed grains during solidification under mechanical stirring, vibration, electromagnetic, electric-current and ultrasonic treatments / N. Balasubramani, J. Venezuela, D. StJohn, G. Wang, M. Dargusch // Journal of Materials Science & Technology. – 2023. – Vol. 144. – P. 243–265. – DOI: 10.1016/j.jmst.2022.09.067.Zhang H., Wu M., Rodrigues C.M.G., Ludwig A., Kharicha A., Rónaföldi A., Roósz A., Veres Z., Svéda M. Dendrite fragmentation mechanism under forced convection condition by rotating magnetic field during unidirectional solidification of AlSi7 alloy. Acta Materialia, 2022, vol. 241, p. 118391. DOI: 10.1016/j.actamat.2022.118391.Dendrite fragmentation mechanism under forced convection condition by rotating magnetic field during unidirectional solidification of AlSi7 alloy / H. Zhang, M. Wu, C.M.G. Rodrigues, A. Ludwig, A. Kharicha, A. Rónaföldi, A. Roósz, Z. Veres, M. Svéda // Acta Materialia. – 2022. – Vol. 241. – P. 118391. – DOI: 10.1016/j.actamat.2022.118391.Adelian A., Ranjbar K., Reihanian M., Dehmolaei R. Microstructural refinement and mechanical enhancement of Hastelloy X welds via electromagnetic vibration-assisted GTAW. Journal of Materials Research and Technology, 2025, vol. 37, pp. 2750–2763. DOI: 10.1016/j.jmrt.2025.06.213.Microstructural refinement and mechanical enhancement of Hastelloy X welds via electromagnetic vibration-assisted GTAW / A. Adelian, K. Ranjbar, M. Reihanian, R. Dehmolaei // Journal of Materials Research and Technology. – 2025. – Vol. 37. – P. 2750–2763. – DOI: 10.1016/j.jmrt.2025.06.213.