Orenburg State University, Orenburg, Russia:
S. I. Bogodukhov, Dr. Eng., Prof., Dept. of Materials Science and Technology of Materials, e-mail: ogu@mailgate.ru
E. S. Kozik, Cand. Eng., Associate Prof., Dept. of Materials Science and Technology of Materials, e-mail: ele57670823@yandex.ru
E. V. Svidenko, Cand. Eng., Associate Prof., Dept. of Materials Science and Technology of Materials, e-mail: tzvetkova.katia2016@yandex.ru
A. A. Nepoklonnova, Postgraduate Student, Dept. of Industrial Automation Systems, e-mail: anasknastya@yandex.ru

In this paper, the method of continuous laser exposure, in particular laser treatment, is considered. Bushings (D_nar = 22 mm, d_nut = 10.5 mm, H = 16 mm (height of bushings)) made of powder structural material of the PK70 brand were subjected to research. The processing of the bushings was carried out on a laser complex along the upper base of the bushing along the circumference with D = 17 mm. Several factors of laser exposure changed - the speed of movement of the laser beam v, the radiation power of the laser beam P, with a constant diameter of the radiation beam D. Before carrying out metallographic analyses, the samples were sanded, polished and etched. To study the microstructure outside the laser treatment zone, study zones from 2 to 4 mm from the impact zone were determined. The microstructure of the powder material PK70 (initial) and after laser quenching has been studied. The microstructure of the PC 70 powder material outside the laser hardening zone is pearlite-ferritic. The hardness and microhardness of the powder material were measured.

1. Ermakov S. S., Vyaznikov N. F. Powder steels and articles. 4^th edition revised and enlarged. Leningrad: Mashinostroenie. Leningradskoe otdelenie, 1990. 319 p.
2. Bogodukhov S. I., Suleymanov R. М., Proskurin А. D. Technological processes in mechanical engineering: textbook. for universities. General editorship: S. I. Bogodukhov. Moscow: Innovatsionnoe mashinostroenie, 2021. 640 p.
3. Ye Tur-ming, Yi Jian-hong, Chen Shi-jin, Peng Yuan-dong, Li Li-ya, Xia Qing-lin. Die wall lubricated warm compaction behavior of non-lubricant admixed iron powders. Journal of Central South University of Technology. 2005. Vol. 12, Iss. 6. pp. 653–656.
4. Bogodukhov S. I., Kozik Е. S., Garipov V. S. Planning experiments for heat treatment of products from powder steels in electrolytes. Chernye Metally. 2023. No. 1. pp. 52–57.
5. Churnosov D. I., Kozik Е. S., Golyavin К. А. Surface hardening of workpieces from powder steels using laser heating. Vestnik Orenburgskogo gosudarstvennogo universiteta. 2013. No. 1 (150). pp. 228–232.
6. 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.
7. Laser technologies for material processing: current problems of fundamental research and applied development. Edited by V. Ya. Panchenko. Moscow: Fizmatlit, 2009. 664 p.
8. 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.
9. Karfidov А. О., Chicheneva О. N., Pashkova А. N., Gorovaya Т. Yu. Technological factors of laser hardening of rolls of multi-roll mills. Metallurg. 2022. No. 12. pp. 53–62.
10. Skripchenko А. I., Popov V. О., Kondratev S. Yu. Possibilities of laser surface modification of machine building parts. RITM. 2010. No. 6. pp. 23–29.
11. Yi-Wen Tai, Cheng-Hsin Chen. Transflective TFT LCD having stacked layers including a protective layer, a transparent electrode and a ring-shaped reflective electrode surrounding and defining an opening exposing the underlying transparent electrode layer. Patent USA, No. 7724327. Applied: 10.05.2005. Published: 10.07.2007.
12. Zhulin A. N., Gay A. V., Rassadin M. Yu. Antifriction powdery material. Patent RF, No. 2268440. Applied: 03.02.2005. Published: 20.01.2006. Bulletin No. 19.
13. Bogodukhov S. I., Kozik Е. S., Svidenko Е. V., Ignatyuk V. D. Influence of continuous laser action on powder materials. DGP 2020. Hot pressing, fundamental and applied aspects of obtaining powder and composite materials, coatings: Proceedings of the International scientific and technical conference dedicated to 85th birthday of professor Yu. G. Dorofeev, June 22–24, 2020, Novocherkassk. Electron data. Novocherkassk: NOK, 2020. pp. 175–182.