Study of the Behavior of a Particle of Diffusion-Alloyed Powder of Austenitic Steel in a Plasma Jet during Spraying

Currently, a significant number of parts and equipment break down as a result of wear processes. To solve this problem, restoration and strengthening technologies, in particular plasma spraying of coatings, are widely used. The material that allows plasma spraying to produce high-quality coatings is diffusion-alloyed powder made from 12X18H10 (12Kh18N9) austenitic steel. Since powders of this type have not been previously used for plasma spraying, we developed a theoretical model for the rupture of the crust of a refractory compound (iron boride), which was formed on the surface of a powder particle during diffusion alloying, due to the melting of the particle core during heating in a plasma jet. The model determines the condition under which the crust rupture occurs, which can ensure the spreading of the melt over the surface of the workpiece and the formation of a high-quality coating. To confirm the model, an experimental study of the powder particle behavior in a plasma jet during spraying was carried out. On the basis of the data obtained as a result of the experiment and the results of calculations according to the developed model, a mechanism for the behavior of a diffusion-alloyed austenitic steel particle in a plasma jet is proposed and requirements for powder particles are determined. It was found that the particles should be small enough so that when flying in the plasma jet they could be heated through and the iron core would melt. In our case the size of the diffusion-alloyed particles must be within 40–80 μm. Also, for the correct process of plasma spraying and the formation of a plasma-sprayed coating with low porosity, the outer boride layer must have a small thickness relative to the particle radius so that when the core melts in the plasma jet, the boride crust cracks and the melt begins to flow out. For particles with a diameter of 40–80 μm, this ratio is ensured by diffusion alloying during 3 hours.

1. Espallargas N. (ed.). (2015) Future Development of Thermal Spray Coatings: Types, Designs, Manufacture and Applications. 1st ed. Woodhead Publishing. 300. https://doi.org/10.1016/C2013-0-16360-X.

2. Vardelle A., Moreau C., Akedo J., Ashrafizadeh H., Berndt C. C., Berghaus J. O. (2016) The 2016 Thermal Spray Roadmap. Journal of Thermal Spray Technology, 25 (8), 1376–1440. https://doi.org/10.1007/s11666-016-0473-x.

3. Samukawa S., Hori M., Rauf S., Tachibana K., Bruggeman P., Kroesen G. (2012) The 2012 Plasma Roadmap. Journal of Physics D: Applied Physics, 45 (25), 253001. https://doi.org/10.1088/0022-3727/45/25/253001.

4. Konstantinov V. M., Spiridonov N. V., Devoino O. G., Avsievich A. M., Kanstantsіnaў V. M., Spіrydonaў M. V., Aўsіevіch A. M., Panteleenko F. I. (2005) Wear-Resistant Gas-Thermal Coatings Made of Diffusion-Alloyed Powders Based on Cast Iron Chips. Minsk, Tekhnoprint Publ. 146 (in Russian).

5. Konstantinov V. M., Frutsky V. A. (2003) Relationship between the Structure and Properties of Antifriction Gas-Thermal Coatings Made of Boron-Copper-Plated Cast Iron Chips. Vestnik Polotskogo Gosudarstvennogo Universiteta. Ser. B, Prikladnye Nauki [Bulletin of Polotsk State University. Series B, Applied Scienes], (2), 7–11 (in Russian).

6. Panteleenko F. I., Snarsky A. S. (1997) Features of Tribological Behavior of a Pair of Boron-Containing Tool Material – Part. Trenie i Iznos = Friction and Wear, 18 (4), 518–522 (in Russian).

7. Konstantinov V. M., Panteleenko F. I., Frutsky V. A., Sorogovets V. I. (2004) Tribological and Thermophysical Properties of Gas-Thermal Coatings from Diffusion-Alloyed Cast Iron Chips. Trenie i Iznos = Friction and Wear, 25 (2), 190–196 (in Russian).

8. Petrishin G. V., Panteleenko E. F., Panteleenko A. F. (2006) Diffusion-Alloyed Steel Powder for Magnetic-Electric Hardening. Uprochnyayushchie Tekhnologii i Pokrytiya = Strengthening Technologies and Coatings, (4), 26–31 (in Russian).

9. Avsievich A. M., Spiridonov N. V., Konstantinov V. M. (2002) Wear Resistance of Plasma-Sprayed Coatings from Diffusion-Alloyed Iron-Based Self-Fluxing Powders. Journal of Friction and Wear, 23 (5), 43–47.

10. Panteleenko A. F., Devoyno O. G. (2013) Chapter 28. Composite Coatings Obtained by High-Energy Methods. Klubovich V. V. (ed.). Advanced Materials and Technologies. Vitebsk, Publishing House of Vitebsk State Technological University, 587–607 (in Russian).

11. Storozhuk N. V., Gusak A. M. (2014) Competition Between the Frenkel and Kirkendall Effects in Mutual Diffusion. Metallofizika i Noveyshie Tekhnologii = Metallophysics and Advanced Technologies, 36 (3), 367–374 (in Russian). https://doi.org/10.15407/mfint.36.03.0367.

12. Feng J., Xiao B., Zhou R., Jiang Y. H., Cen Q. H. (2012) Calculation and Simulation for the Mechanical Properties of Carbides and Borides in Cast Iron. Procedia Engineering, 31, 676–681. https://doi.org/10.1016/j.proeng.2012.01.1085.

13. Gou Y., Fu Z., Liang Y., Zhong Z., Wang S. (2014) Electronic Structures and Mechanical Properties of Iron Borides From First Principles. Solid State Communications, 187, 28–32. https://doi.org/10.1016/j.ssc.2014.02.019.

14. Culha O., Toparli M., Aksoy T. (2009) Estimation of FeB Layer’s Yield Strength by Comparison of Finite Element Modeling with Experimental Data. Advances in Engineering Software, 40 (11), 1140–1147. https://doi.org/10.1016/j.advengsoft.2009.05.005.

15. Khina B. B., Formanek B., Solpan I. (2005) Limits of Applicability of the “Diffusion-Controlled Product Growth” Kinetic Approach to Modeling SHS. Physica B: Condensed Matter, 355 (14), 14–31. https://doi.org/10.1016/j.physb.2004.09.104.

16. Landau L. D., Lifshits E. M. (1987) Theory of Elasticity. 4th ed. Moscow, Nauka. Main Editorial Board of Physical and Mathematical Literature. 248 (in Russian).

17. Massalski T. B., Murray J. L., Bennett L. H., Baker H. (eds.). (1990) Binary Alloy Phase Diagrams. 2nd ed. Ohio, ASM International, Metals Park. 3589 p.

18. Takamichi I., Guthrie R. I. L. (2015) The Thermophysical Properties of Metallic Liquids. Vol. 1: Fundamentals. Oxford University Press. 353. https://doi.org/10.1093/acprof:oso/9780198729839.003.0001.

19. Brandes E. A., Brook G. B. (eds.). (1992) Smithells Metals Reference Book. 7th ed. Oxford, Butterworth-Heinemann. 1794. https://doi.org/10.1016/C2009-0-25363-3.