Nanostructuring of the Surface Layer of Roller Knives to Increase Their Resistance to Wear and Corrosion

The work investigated roller knives made of tool steel X12MF with a nickel–copper coating applied by diffusion alloying and subsequent intensive plastic deformation (IPD) with contact stresses from 3.0 to

4.5 GPa. The following methods were used: optical and transmission electron microscopy; X-ray diffraction and microrentgenospectral analysis. Tribological and corrosion tests, measurements of microhardness and roughness were carried out. It is shown that after applying Ni–Cu coating and IPD at a voltage of 3.5 GPa, there was not only a decrease by 2 times in the coefficient of friction, 2.1 times wear, 2.5 times the roughness of the roller surface, compared with uncoated steel, but also an increase in the setting load to 1400 N. At the same time, a dislocation substructure was formed in the coating with a minimum size of 23 nm coherent scattering regions and a maximum value of 1.25 % microdeformation of the crystal lattice, which indicated the presence of large elastic distortions of the crystal lattice. The transverse size of dislocation subgrains (small areas inside the crystalline grains, separated by small-angle boundaries, which consist of dislocation grids formed during deformation and creating an internal substructure) (35—47 nm) decreased by 5 times compared to the initial state (200—256 nm). In the high-resolution mode, the presence of predominantly small-angle boundaries in the coating structure was detected, which had a greater penetrating ability to redistribute alloying elements. It can be assumed that chromium from steel X12MF, being in solid solution, was redistributed along the small-angle dislocation boundaries of the elongated polygonized nanostructure. In the coating, an increase in the concentration of Cr, compared with the initial state, led to an increase in its relative resistance to wear and corrosion.

1. Ivanov E.K., Skotnikova M.A., and Krylov N.A. Structural Phase Changes in the Hardly Processed Materials as a Way of Increase of Wear Resistance of the Tool // Scientific and Technical Sheets SPBGPU. Science and Education. — 2012, no. 1, 41—52

2. Skotnikova M.A. and Krylov N.A. About the Nature of Dissipative Processes in Cutting Treatments of Titanium Vanes // Advances in Mechanical Engineering. — Springer International Publishing. — 2017, 115—123

3. Bobylev E.E., Storozhenko I.D., Matorin A.A., et al. Specific Features of the Formation of Ni–Cr Coatings Prepared by Diffusion Alloying from Low-Melting Liquid-Metal Solutions // Russ. Metall. — 2024, 1841—1848

4. Mohammad Reza Najari, Seyed Abdolkarim Sajjadi, and Omid Ganji. Microstructural Evolution and Wear Properties of Chromium Carbide Coating Formed by Thermo-Reactive Diffusion (TRD) Process on a Cold-Work Tool Steel // Results in Surfaces and Interfaces. — 2022 (8), 100059.

5. Maskavizan A.J., Quintana J.P., Dalibón E.L., et al. Evaluation of Wear and Corrosion Resistance in Acidic and Chloride Solutions of Cathodic Arc PVD Chromium Nitride Coatings on Untreated and Plasma Nitrided AISI 4140 Steel // Surface and Coatings Technology. — 2024 (494), no. 3, 131476

6. Fedrizzi L., Rossi S., Bellei F., et al. Wear-Corrosion Mechanism of Hard Chromium Coatings // Wear. — 2002 (253), no. 11/12, 1173—1181

7. Pryakhin E.I., Mikhailov A.V., and Sivenkov A.V. Technological Features of Surface Alloying of Metal Products with Cr–Ni complexes in the medium of Low-Melting Metal Melts // Ferrous Metals. — 2023, no. 2, 58–—66 (in Russian)

8. Yusuf Kayali and Afra Kenar. Effect of Diffusion Annealing on Wear and Cohesion Behaviours of Boronized AISI 1040 Steel // Tribology International. — 2023 (184), 108428

9. Jing Liang, Ye Liu, Sheng Yang, et al. Microstructure and Wear Resistance of Laser Cladding Ti-Al-Ni-Si Composite Coatings // Surface and Coatings Technology. — 2022 (445), 128727

10. Vikrant Singh, Anil Kumar Singla, and Anuj Bansal. Impact of HVOF Sprayed Vanadium Carbide (VC) Based Novel Coatings on Slurry Erosion Behavior of Hydro-Machinery SS316 Steel // Tribology International. — 2022 (176), 107874

11. Xiang Hou, Hao Wang, Qun Yang, et al. Microstructure and Properties of Cr-AlN Composite Coating Prepared by Pack-Cementation on the Surface of Al-Containing ODS Steel // Surface and Coatings Technology. — 2022 (447), 128842

12. Ustrojstvo dlya diffuzionnoj metallizacii v srede legkoplavkih zhidkometallicheskih rastvorov: Patent RF № 2423546. Zayavleno 08.12.2009.; Opublikovano 10.07.2011. — Byul. № 19 / Sokolov A.G., Artem'ev V.P., Shasherina S.A. (in Russian)

13. Sposob formirovaniya na poverhnosti stal'nogo izdeliya nanostrukturirovannogo sloya: Patent RF № 2413037. Zayavleno 06.08.2009.; Opublikovano 27.02.2011. — Byul. № 6 / A.G. Sokolov, S.A. Shasherina, V.P. Artem'ev (in Russian)

14. Zhmurkin S.Yu., Averin I.A., Pronin I.A., Karmanov A.A. Metodika rascheta razmerov oblastej kogerentnogo rasseyaniya v materialah s sil'noj deformaciej kristallicheskoj reshetki // Vestnik Penzenskogo gosudarstvennogo universiteta. — 2017 (17), № 3, 55—60 (in Russian)

15. Malygin G.A. Vliyanie razmera zeren na ustojchivost' mikro i nanokristallicheskih metallov k lokalizacii plasticheskoj deformacii v vide shejki // Fizika tverdogo tela. — 2011 (53), № 2, 341—345 (in Russian)