ArticleName |
The effect of laser hardening on the operation resistance of rolls of multi-roll mills and
the quality of the rolling strip |
ArticleAuthorData |
National University of Science and Technology “MISIS” (Moscow, Russia)
N. A. Chichenev, Dr. Eng., Prof., Dept. of Engineering Technology Equipment, e-mail: chich38@mail.ru M. V. Vasilyev, Senior Lecturer, Dept. of Engineering Technology Equipment, e-mail: mv@karfidovlab.com A. O. Karfidov, Head of Dept. of Engineering Technology Equipment, e-mail: a.korf@mail.ru O. N. Chicheneva, Cand. Eng., Associate Prof., Dept. of Engineering Technology Equipment, e-mail: ch-grafika@mail.ru |
Abstract |
The results of experimental studies of the process of laser hardening of rolls of multi-roll mills during linear and spiral hardening of samples from Kh9VMFSh steel are presented. It was found that during linear laser treatment, the depth of the hardened layer significantly depends on the power of laser radiation and the speed of translational motion of samples; at the same time, it weakly depends on the diameter of the laser beam. Corresponding graphs, which are more convenient for practical use for selection of technological modes of laser processing, have been built. With spiral laser hardening, the surface of axisymmetric parts is subjected to cyclic heating, the number of cycles of which depends on the speed of translational motion and rotation speed. It is established that decrease of the temperature of the surface layers of the part heated by laser radiation practically does not occur due to thermal conductivity at a sufficiently high value of the rotation speed. It is shown that increase of the rotation speed of samples from 1,000 to 10,000 min-1 leads to increase of the depth of the hardened layer from 0.72 to 1.60 mm with a slight enlargement of hardness of the surface layers, while the depth of the hardened layer significantly depends on the speed of translational motion of the samples and their diameter; it should be taken into account when developing technological modes of laser hardening. Pilot-industrial tests of working rolls during rolling of the strip with 0.012×200 mm cross-section, made from L63 brass, showed that the surface purity of the rolled strip increased from the 7th to the 8th class of roughness, and the number of breaks decreased by 1.5-1.8 times. When rolling a strip of nickel NP-2 at a 20-roll mill 300, it was found that consumption of rolls that have been subjected to laser processing is 2 times less than consumption of volume-hardened rolls, while transverse thickness has decreased to ± 3 % (compared with ± 5 % during rolling in volume-hardened rolls). |
References |
1. Jiang Z. Y., Wei D., Tieu A. K. Analysis of cold rolling of ultrathin strip. Journal of Materials Processing Technology. 2009. Vol. 209. No. 9. pp. 4584–4589. 2. Sheikhi Sh., Angerbauer A., Wuppermann C.-D. Developments in flat steel production. Chernye metally. 2010. No. 1. pp. 30-37. 3. Ritterbach B. Trends in steel research. Chernye metally. 2014. No. 9. pp. 75-78. 4. Wu Y. L Discussion on the key points of cold rolling process. Enterprise Guide. 2015. Vol. 20. pp. 49-51. 5. Rumyantsev M. I. Some approaches to improve the resource efficiency of production of flat rolled steel. CIS Iron and Steel Review. 2016. Vol. 12. pp. 32-36. 6. Sudakov N. V., Pellenen A. P. Reserves of cold sheet rolling. Metallurg. 2018. No. 11. pp. 47-51. 7. Aljabri A., Jiang Z., Wei D. Analysis of thin strip profile by work roll crossing and shifting in asymmetrical cold rolling. Advanced Materials Research. 2014. Vol. 894. pp. 212–216. 8. Tibar H., Jiang Z. Improving Thin Strip Profile Using Work Roll Cross and Work Roll Shifting Methods in Cold Strip Rolling. International Journal of Metals. 2017. Article ID 6489769. DOI: 10.1155/2017/6489769 9. Liu X., Xia H. Theoretical and experimental study on the producible rolling thickness in ultra-thin strip rolling. Journal of Materials Processing Technology. 2020. Vol. 278. 116537. 10. Mazur V. L., Nogovitsyn O. V. Theory and Technology of Sheet Rolling: Numerical Analysis and Applications. CRC Press: Boca Raton, Florida, USA. 2019. 494 pp. DOI: 10.1201/9781351173964 11. Parshin S. V. Innovative solutions for constructions of 20-roll mills: A manual. Ekaterinburg: Izdatelstvo Uralskogo universiteta. 2016. 76 p. 12. Polukhin V. P., Bernshtein M. L., Pimenov A. F. et al. Rolls of multi-roll mills. Moscow: Metallurgiya. 1983. 129 p. 13. Smirnov A. E. Control of phase composition in complex-alloyed heat-resistant steels during vacuum cementation and quenching. Metallovedenie i termicheskaya obrabotka metallov. 2020. No. 9 (783). pp. 45–52. 14. Metal science and heat treatment of steel and cast iron: Reference book in 3 volumes. Vol. 3. Heat and thermomechanical treatment of steel and cast iron. Edited by Rakhshtadt A. G., Kaputkina L. M., Prokoshkin S. D., Supov A. V. 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. DOI: 10.1016/j.jmapro.2019.08.020 16. Khorram A., Davoodi Jamaloei A., Jafari A., Moradi M. YAG laser surface hardening of AISI 431 stainless steel; mechanical and metallurgical investigation. Optics and Laser Technology. 2019. Vol. 119. Article No. 105617. DOI: 10.1016/j.optlastec.2019.105617 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 A. G., Shiganov I. N., Misyurov A. I. Technological processes of laser treatment: A manual. Moscow: Izdatelstvo MGTU im. N. E. Baumana. 2006. 663 p. 19. Laser technologies for materials processing: the modern problems of fundamental researches and applied developments. Edited by Panchenko V. Ya. Moscow: FIZMATLIT. 2009. 664 p. 20. Veremeevich A. N., Beletskiy V. V., Ivanov S. A. On the problem of heat treatment of rolls in multi-roll mills. Izvestiya vuzov. Chernaya metallurgiya. 1986. No. 11. pp. 157-158. 21. Chichenev N. A., Chicheneva O. N., Karfidov A. O., Pashkov A. N. Selection of laser processing parameters for hot stamping tools based on mathematical planning of the experiment. CIS Iron and Steel Review. 2021. Vol. 22. pp. 37-40. 22. Bardovskiy A. D., Gerasimova A. A., Bibikov P. Ya. Principles of improvement of milling equipment. Gornyi zhurnal. 2020. No. 3. pp. 56-59. |