National University of Science and Technology “MISiS”, Moscow, Russia:

N. A. Chichenev, Dr. Eng., Prof., Dept. of Engineering of Technological Equipment, e-mail: chich38@mail.ru
A. O. Karfidov, Head of Dept. of Engineering of Technological Equipment, e-mail: a.korf@mail.ru
M. V. Vasiliev, Senior Lecturer, Dept. of Engineering of Technological Equipment, e-mail: mv@karfidovlab.com
O. N. Chicheneva, Cand. Eng., Associate Prof., Dept. of Computer-Aided Engineering and Design, e-mail: ch-grafika@mail.ru

The influence of the stamping frequency on the temperature conditions of the press machine knives made of carbon tool steel U8 is considered. The results of a theoretical study of the temperature field of cutting knives on the basis of a numerical solution of a two-dimensional non-stationary differential equation of thermal conductivity with nonlinear thermophysical characteristics are presented. Mathematical modeling of the thermal state of the knives of the press machine shows that the stationary temperature regime on the working surfaces of the knives is established after 20–40 cycles. At the same stamping frequency, the number of cycles corresponding to the output to stationary mode is inversely proportional to the thickness of the band and the strength characteristics of the strip material. It is established that the most unfavorable temperature conditions take place in the near-surface layer with a thickness of 0.1–0.5 mm; when moving away from the surface, the maximum temperature value decreases rapidly, and the amplitude of temperature fluctuations is close to zero. Analysis of the temperature conditions of operation of cold-deformed knives showed that the temperature of their working surface does not reach values exceeding the release temperature after hardening A_otp (for steel U8 – A_otp = 240–270 °С) and therefore in the process of segment spontaneous release does not occur, thereby maintaining their good performance.

1. Efremov D. B., Stepanov V. М., Chicheneva О. N. Modernization of the mechanism for quick pressing out of rolls of the rolling DUO stand of the JSC Ural Steel`s 2800 mill. Stal. 2020. No. 8. pp. 44−47.
2. Nefedov А. V., Tanchuk А. V., Chichenev N. А. Modification of car tippler drive at Donskoy Ore Mining and Processing Plant. Gornyi Zhurnal. 2022. No. 8. pp. 52–56.
3. Samusev S. V., Fadeev V. А., Sidorova Т. Yu. Development of effective calibrations for forming sheet blanks for the production of longitudinally welded pipes of small and medium diameters. Metallurg. 2020. No. 7. pp. 55−57.
4. Busygin A. M., Stelmakhov A. A. Mathematical model for determining kinematic parameters of a bulldozer ripper mechanism. Proceedings of the 8^th International Conference on Industrial Engineering. ICIE 2022. Lecture Notes in Mechanical Engineering. Springer, Cham. 2023. DOI: 10.1007/978-3-031-14125-6_14
5. Bardovskiy A. D., Gorbatyuk S. M., Keropyan A. M., Bibikov P. Ya. Assessing parameters of the accelerator disk of a centrifugal mill taking into account features of particle motion on the disk surface. Journal of Friction and Wear. 2018. Vol. 39, Iss. 4. pp. 326–329.
6. Chichenev N. А. Reengineering of the device for centering the slab in the mill stand. Metallurg. 2018. No. 7. pp. 76−80.
7. Nefedov A. V., Svichkar V. V., Chicheneva O. N. Re-engineering of equipment to feed the melting furnace with aluminum charge. Proceedings of the 6^th International Conference on Industrial Engineering (ICIE 2020). Lecture Notes in Mechanical Engineering. Springer, Cham. 2021. DOI: 10.1007/978-3-030-54817-9_139
8. Gorbatyuk S. М., Morozova I. G., Naumova М. G. Development of a working model of the reindustrialization of the heat treatment of die steels. Izvestiya vuzov. Chernaya metallurgiya. 2017. Vol. 60. No. 5. pp. 410–415.
9. Nefedov A. V., Kitanov А. А., Chichenev N. А. Reengineering of the roller hardening machine of the sheet-rolling shop of JSC Ural Steel. Chernye Metally. 2022. No. 5. pp. 22–26.
10. Konstantinov I. L., Sidelnikov S. B. Forging and stamping production: textbook. Moscow: NITs INFRA-M, 2021. 464 p.
11. Rogov V. А., Poznyak G. G. Engineering technology. Stamping and foundry production: textbook. Moscow: Izdatelstvo Yurayt, 2022. 319 p.
12. Zhivov L. I., Ovchinnikov А. G., Skladchikov Е. N. Forging and stamping equipment: textbook. Edited by L. I. Zhivov. Moscow: Izdatelstvo MGTU imeni N. E. Baumana, 2006. 560 p.
13. Bocharov Yu. А. Forging and stamping equipment: textbook. Moscow: Akademiya, 2008. 479 p.
14. Metal science and heat treatment of steel and cast iron: reference book. In 3 volumes. Vol. 3. Edited by А. G. Rakhshtadt, L. М. Kaputkina, S. D. Prokoshkin, А. V. Supov. Moscow: Intermet Inzhiniring, 2007. 919 p.
15. Maharjan N., Zhou W., Zhou Y., Wu N. Underwater laser hardening of bearing steels. Journal of Manufacturing Processes. 2019. Vol. 47. pp. 52−61.
16. Khorram A., Davoodi J. A., Jafari A., Moradi M. Nd:YAG laser surface hardening of AISI 431 stainless steel; mechanical and metallurgical investigation. Optics and Laser Technology. 2019. Vol. 119. 105617.
17. Chichenev N. A., Gorbatyuk S. M., Naumova M. G., Morozova I. G. Using the similarity theory to describe laser hardening processes. CIS Iron and Steel Review. 2020. Vol. 19. pp. 44-47.
18. Grigoryants А. G., Shiganov I. N., Misyurov А. I. Technological processes of laser processing: textbook. Moscow: Izdatelstvo MGTU imeni N. E. Baumana, 2006. 663 p.
19. Laser technologies for material processing: current issues of fundamental research and applied development. Edited by V. Ya. Panchenko. Moscow: FIZMATLIT, 2009. 664 p.
20. Tool carbon steel U8. Available at: https://www.lsst.ru/spravochnik-metalloprokata/instrumentalnaya-stal/stal-u8/ (Accessed: 04.12.2022).
21. Characteristics of the material U8. Available at: https://www.m-invest.ru/spravochniki/marochnik-staley/stal-instrumentalnaya-uglerodistaya/u8/ (Accessed: 04.12.2022).
22. Sheet punching machine with bottom AB6224 drive. Available at: https://mashinform.ru/kpo/avtomaty/ab6224.shtml (Accessed: 06.01.2023)
23. Yakovlev S. S. Forging and stamping. In 4 volumes. Vol. 4. Sheet stamping. Moscow: Mashinostroenie, 2010. 732 p.
24. Korolev А. А. Rolling mills and equipment for rolling shops. Moscow: Metallurgiya, 1981. 203 p.
25. GOST 1050–2013. Metal products from nonalloyed structural quality and special steels. General specification. Moscow: Standartinform, 2014. 36 p.
26. Tikhonov А. N., Samarskiy А. А. Equations of mathematical physics: textbook. 7^th edition, reprint. Moscow: MGU imeni M. V. Lomonosova, 2004. 800 p.
27. Thambynayagam R. K. M. The diffusion handbook: applied solutions for engineers. McGraw-Hill Professional, 2011. 2048 p.
28. Tkachenko L. А., Repina А. V. Heat transfer theory: textbook. Kazan: Izdatelstvo Kazanskogo universiteta, 2017. 151 p.