Influence of manganese alloying on the structure and properties of electrospark coatings of EP741NP heat-resistant nickel LPBF alloy

The paper investigates the impact of Mn content (Mn = 0; 0.5; 0.6; 1; 1.5 at.%) in the composition of the electrodes of the Al–Ca–Mn system on the structure and properties of electrospark coatings formed on LPBF substrates made of EP741NP alloy. It was found that the highest weight gain of the substrate (5.8·10^–4 g) was recorded when the Al–7%Ca–1%Mn electrode with a low degree of supercooling of the melt (Δt = 5 °C) was subject to electrospark treatment (EST). EST with this electrode with a fine eutectic structure enables the formation of coatings with minimal surface roughness (Ra = 3.51±0.14 μm). The nanocrystalline structure of the coatings was confirmed by transmission electron microscopy, including HRTEM. Comparative tribological tests revealed that the coating with maximum hardness (10.7±0.8 GPa) formed during EST with an electrode containing 1.5 at.% Mn had the minimal wear rate (1.86 ·10^–5 mm³/(N· m)). We proved that EST with Al–Ca–Mn electrodes enables to reduce the specific weight gain of the LPBF EP741NP alloy during isothermal (t = 1000 °C) curing in air due to in situ formation of a complex thermal barrier layer consisting of oxides (α-Al₂O₃, CaMoO₄) and intermetallides (γ ′-Ni₃Al and β-NiAl). We determined the concentration limit of Mn (1.0 at.%) in the electrode, at which the barrier layer retains its integrity and functionality.

1. De Barbadillo J.J. 14-Inconel alloy 740H. (Ed. A.Di Gianfrancesco). In: Materials for ultra-supercritical and advanced ultra-supercritical power plants. Sawston, Cambridge: Woodhead Publ., 2017. Р. 469—510. https://doi.org/10.1016/B978-0-08-100552-1.00014-2

2. Barella S., Boniardi M., Cincera S., Pellin P., Degive X., Gijbels S. Failure analysis of a third stage gas turbine blade. Engineering Failure Analysis. 2011;18(1):386—393. https://doi.org/10.1016/j.engfailanal.2010.09.017

3. Yang M., Zhou Y., Yang J., Bao J., Wang D., Yu Q. Performance analysis of an efficient waste heat utilization system in an ultra-supercritical coal-fired power plant. Energy Reports. 2022;8: 5871—720. https://doi.org/10.1016/j.egyr.2022.04.044

4. Peng J.Q., Zhang H.T., Li Y.F. Review of blade materials for IGT. Procedia Engineering. 2015;130:668—675. https://doi.org/10.1016/j.proeng.2015.12.295

5. Liang F., Meng A., Sun Y., Chen Zh., Jiang Zh., Zhang Y., Zhang Y., Zhu Y., Chen X. A novel wear-resistant Nibased superalloy via high Cr-induced subsurface nanotwins and heterogeneous composite glaze layer at elevated temperatures. Tribology International. 2023;183:108383. https://doi.org/10.1016/j.triboint.2023.108383

6. Kamalan Kirubaharan A.M., Kuppusami P., Ghosh Ch., Priya R., Ningshen S., Dinesh Kumar D., Divakar R. Metal-ceramic diffusion barrier nanocomposite coatings on nickel based superalloys for corrosion and high temperature oxidation resistance. Ceramics International. 2022;48:31281—31288. https://doi.org/10.1016/j.ceramint.2022.06.203

7. Sanin V.V., Aheiev M.I., Kaplanskii Y.Y., Loginov P.A., Bychkova M.Y., Levashov E.A. The effect of dopants on structure formation and properties of cast SHS alloys based on nickel monoaluminide. Materials. 2023;16(9):3299. https://doi.org/10.3390/ma16093299

8. Kurzynowski T., Smolina I., Kobiela K., Kuźnicka B., Chlebus E. Wear and corrosion behaviour of Inconel 718 laser surface alloyed with rhenium. Materials & Design. 2017;132:349—359. https://doi.org/10.1016/j.matdes.2017.07.024

9. Behera A., Sahoo A.K. Wear behaviour of Ni based superalloy: A review. Materials Today: Proceedings. 2020;33(8):5638—5642. https://doi.org/10.1016/j.matpr.2020.04.007

10. Yu W., Ming W., An Q., Chen M. Cutting performance and wear mechanism of honeycomb ceramic tools in interrupted cutting of nickel-based superalloys. Ceramics International. 2021;47(13):18075—18083. https://doi.org/10.1016/j.ceramint.2021.03.123

11. Campos-Silva I., Contla-Pacheco A.D., Figueroa-López U., Martínez-Trinidad J., Garduño-Alva A., Ortega-Avilés M. Sliding wear resistance of nickel boride layers on an Inconel 718 superalloy. Surface and Coatings Technology. 2019;378:124862. https://doi.org/10.1016/j.surfcoat.2019.06.099

12. Yang Sh., Gao S., Xue W., Wu B., Cheng H., Duan D. Epitaxial growth and oxidation behavior of the NiCoCrAlYTa/Y2O3 coating on a nickel-based single— crystal superalloy blade tips, produced by electro spark deposition. Journal of Alloys and Compounds. 2023;931:167600. https://doi.org/10.1016/j.jallcom.2022.167600

13. Balaguru S., Gupta M. Hardfacing studies of Ni alloys: A critical review. Journal of Materials Research and Technology. 2021;10:1210—1242. https://doi.org/10.1016/j.jmrt.2020.12.026

14. Jude S.A.A., Winowlin Jappes J.T., Adamkhan M. Thermal barrier coatings for high-temperature application on superalloy substrates — A review. Materials Today: Proceedings. 2022;60:1670—1675. https://doi.org/10.1016/j.matpr.2021.12.223

15. Darolia R. Thermal barrier coatings technology: Critical review, progress update, remaining challenges and prospects. International Materials Reviews. 2013;58(6):315— 348. https://doi.org/10.1179/1743280413Y.0000000019

16. Jayalakshmi V., Subramanian K.R.V. Thermal barrier coatings: state-of-art developments and challenges: A mini review. Transactions of the IMF. 2022;100(1):6—9. https://doi.org/10.1080/00202967.2021.1979813

17. Evans A.G., Clarke D.R., Levi C.G. The influence of oxides on the performance of advanced gas turbines. Journal of the European Ceramic Society. 2008;28(7): 1405—1419. https://doi.org/10.1016/j.jeurceramsoc.2007.12.023

18. Mukanov S.K., Baskov F.A., Petrzhik M.I., Levashov E.A. Electro-spark treatment with low-melting Al—Si and Al—Ca electrodes in order to improve wear and oxidation resistance of EP741NP alloy prepared by selective laser melting. Metallurgist. 2022;66(3-4):317—326. https://doi.org/10.1007/s11015-022-01331-0

19. Junwei Fu, Kai Cui Effect of Mn content on the microstructure and corrosion resistance of Al—Cu—Mg—Mn alloys. Journal of Alloys and Compounds. 2022;896:162903. https://doi.org/10.1016/j.jallcom.2021.162903

20. Naumova E., Doroshenko V., Barykin M., Sviridova T., Lyasnikova A., Shurkin P. Hypereutectic Al—Ca—Mn— (Ni) alloys as natural eutectic composites. Metals. 2021;11:890. https://doi.org/10.3390/met11060890

21. Petrzhik M., Molokanov V., Levashov E. On conditions of bulk and surface glass formation of metallic alloys. Journal of Alloys and Compounds. 2017;707:68—72. https://doi.org/10.1016/j.jallcom.2016.12.293

22. Arroyo-de Dompablo E., Ponrouch A., Johansson P., Palacín R. Achievements, challenges, and prospects of calcium batteries. Chemical Reviews. 2020;120(14):6331— 6357. https://doi.org/10.1021/acs.chemrev.9b00339

23. Potanin A.Yu., Astapov A.N., Pogozhev Yu.S., Rupasov S.I., Shvyndina N.V., Klechkovskaya V.V., Levashov E.A., Timofeev I.A., Timofeev A.N. Oxidation of HfB2—SiC ceramics under static and dynamic conditions. Journal of the European Ceramic Society. 2021;41(16): 34—47. https://doi.org/10.1016/j.jeurceramsoc.2021.09.018

24. Tian Sh., He A., Liu J., Zhang Y., Yang Y., Zhang Y., Jiang H. Oxidation resistance of TiAl alloy improved by hot-pack rolling and cyclic heat treatment. Materials Characterization. 2021;178:111196. https://doi.org/10.1016/j.matchar.2021.111196

25. Zhou B., He J., Liu L., Wang S., Sun J., Wei L., Guo H. The interaction between Dy, Pt and Mo during the short— time oxidation of (γ ′ + β) two-phase Ni—Al coating on single crystal superalloy with high Mo content. Surface and Coatings Technology. 2022;430:127999. https://doi.org/10.1016/j.surfcoat.2021.127999

26. Bsaibess E., Delorme F., Monot-Laffez I., Giovannelli F. Ultra-low thermal conductivity in scheelite and A-deficient scheelite ceramics. Scripta Materialia. 2021;201:113950. https://doi.org/10.1016/j.scriptamat.2021.113950

27. Ait Laasri H., Bsaibess E., Delorme F., Nataf G.F., Giovannelli F. Ultra-low lattice thermal conductivity in tungsten-based scheelite ceramics. Journal of Alloys and Compounds. 2023;955:170167. https://doi.org/10.1016/j.jallcom.2023.170167

28. Yun D. W., Seo S.M., Jeong H.W., Yoo Y.S. The effects of the minor alloying elements Al, Si and Mn on the cyclic oxidation of Ni—Cr—W—Mo alloys. Corrosion Science. 2014;83:176—188. https://doi.org/10.1016/j.corsci.2014.02.015

29. Zhou B., He J., Peng H., Sun J., Guo H. The influence of Hf content on oxide scale microstructure and HfO2 formation mechanisms in two-phase (γ ′ + β) Ni—Al alloys. Materials Characterization. 2022;184:111659. https://doi.org/10.1016/j.matchar.2021.111659