The Effect of Redox Reactions During Laser Alloying of Steel with Bismuth Oxide on Tribological Characteristics Under Boundary Friction Conditions

This work investigates the tribological characteristics of the surface of carbon steel alloyed with bismuth oxide with the addition of an oxidizer or a reducing agent, specifically lithium nitrate or highly dispersed graphite powder, respectively. Tribological tests were performed in contact with an aluminum alloy AZh1 under boundary lubrication conditions.
It was established that carbon interacts with bismuth oxide during the alloying process under high-temperature laser treatment, leading to the formation of metallic bismuth, which negatively affects the performance of the tribological pair under high contact load. Furthermore, a higher carbon content in the powder mixture results in a greater amount of reduced bismuth oxide in the steel surface and a lower load-carrying capacity of the pair at a constant speed of 9.0 m/s. Conversely, the decomposition of lithium nitrate with the release of oxygen during high-intensity laser processing leads to an increased proportion of oxidized bismuth in the alloyed surface. The addition of the oxidizer significantly improves the tribological characteristics of the pair under boundary lubrication friction conditions. A possible mechanism for the occurrence of ultralow friction and wear coefficients during sliding friction under boundary lubrication for the “bismuth-oxidealloyed steel vs. aluminum alloy” friction pair is proposed.

1. Garkunov D.N. Tribotekhnika (iznos i bezyznosnost'): Uchebnik. 4-e izd. — M.: Iz-vo MSHA. — 2001 (in Russian)

2. Ahmatov A.S. Molecular Physics of Boundary Friction. — Publ. Israel Program for Scientific Translations: University of California. — 1966

3. Kharanzhevskiy E.V. et al. Towards Eliminating Friction and Wear in Plain Bearings Operating without Lubrication // Scientific Reports. — 2023 (13), no. 1, 17362. https://doi.org/10.1038/s41598-023-44702-6

4. Sun H., Gewen Y., Shanhong W., and Peiying S. Effect of Adding Soft Bi2O3 on Structural Modification and Tribological Regulation of Ni-5 wt% Al Composite Coating in Wide Temperatures Range // Surface and Coatings Technology. — 2021 (405), 126517. https://doi.org/10.1016/j.surfcoat.2020.126517

5. Kato H. and Komai K. Tribofilm Formation and Mild Wear by Tribo-Sintering of NanometerSized Oxide Particles on Rubbing Steel Surfaces // Wear. — 2007 (262), nos. 1–2, 36—41. https://doi.org/10.1016/j.wear.2006.03.046

6. Wang X., Feng X., Lu C., Yi G., Jia J., and Li H. Mechanical and Tribological Properties of Plasma Sprayed NiAl Composite Coatings with Addition of Nanostructured TiO2/Bi2O3 // Surface and Coatings Technology. — 2018 (349), 157—165. https://doi.org/10.1016/j.surfcoat.2018.05.055/

7. Rodil S.E., Depablos-Rivera O., and SánchezLópez J.C. Tribological Response of δ-Bi2O3 Coatings Deposited by RF Magnetron Sputtering // Lubricants. — 2023 (11), no. 5, 207. https://doi.org/10.3390/lubricants11050207.

8. Ipatov A.G., Malinin A.V., Shmykov S.N. Increasing the efficiency of ICE turbochargers by modifying bearing matings // Repair. Restoration. Modernization. — 2024, no. 5, 8—12. DOI: 10.31044/1684-2561-2024-0-5-8-12 (in Russian)

9. Ipatov A.G., Shmykov S.N. Synthesis of antifriction coatings by the FABO method // Technical service of machines. — 2021, No. 1(142), 140—147. DOI: 10.22314/2618-8287-2021-59-1-140-147 (in Russian)/

10. Makarov A.V., Kharanzhevsky E.V., Ipatov A.G., Sirosh V.A., Soboleva N.N., and Volkova E.G. The Effect of Wearlessness during Surface Alloying of Steel with Bismuth // Journal of Friction and Wear. — 2024 (45), no. 6, 558—568

11. Makarov A.V., Sirosh V.A., Soboleva N.N., Volkova E.G., Ipatov A.G., Gil`mutdinov F.Z., and Kharanzhevskiy E.V. Ultralow Wear in Boundary Lubrication: a Tribological Study of BiAlloyed Steel under High Normal Loads and Sliding Speeds // Friction. — 2025 (13), no. 7, 9441049. https://doi.org/10.26599/FRICT.2025.9441049

12. Razak M., Liza S., and Fukuda K. Investigation of Surface Morphology, Wettability and Tribological Properties of Ni Composite Coating Added with Graphite // Surf. Topogr.: Metrol. Prop. — 2025, no. 13, 015016. DOI: 10.1088/2051-672X/adad8c

13. Guan L., Zhang Y., Cheng K., and Zhang R. Influence of Graphite on Tribological Properties of SiC/Cu/Gr Composites with SiO2–Cu2O Glass Boundary // Ceramics International. — 2024 (50), no. 9, 15481—15489. https://doi.org/10.1016/j.ceramint.2024.02.025

14. Kharanzhevskiy E.V., Ipatov A.G., Makarov A.V., Gil’mutdinov F.Z., Soboleva N.N., and Krivilyov M.D. Tribological Performance of Boron-Based Superhard Coatings Sliding Against Different Materials // Wear. — 2021 (477), 203835. https://doi.org/10.1016/j.wear.2021.203835/

15. Volkov K.G., Ipatov A.G., Kharanzhevskii E.V., Shmykov S.N. Restoration and Hardening of the Working Chamfer of the Valve of an Internal Combustion Engine by Selective Laser Melting (SLM) // Steel in Translation. — 2023 (53), no. 3, 232—237. DOI: 10.3103/s0967091223030191

16. Yukhin Yu.M., Mikhailov Yu.I. Chemistry of bismuth compounds and materials. — Novosibirsk: SB RAS. — 2001 (in Russian)

17. Ortiz-Quiñonez J.L., Zumeta-Dubé I., Díaz D., Nava-Etzana N., Cruz-Zaragoza E., and Santiago-Jacinto P. Bismuth Oxide Nanoparticles Partially Substituted with EuIII, MnIV, and SiIV: Structural, Spectroscopic, and Optical Findings // Inorg Chem. — 2017, Mar 20; (56), no. 6, 3394—3403. doi: 10.1021/acs.inorgchem.6b02923. Epub. 2017 Mar 2. PMID: 28252972