Research into the Structure and Adhesion of WCCoCr Coatings Plasma-Sprayed onto Castings of AlSi Alloy Plates
DOI:
https://doi.org/10.24425/afe.2024.151294Abstract
The article presents structural investigations and mechanical properties of hard coatings deposited by spraying WCCoCr powder in an argon hydrogen plasma jet onto the surfaces of AlSi10Mg alloy casting plates. Two variants (A and B) of processing parameters of the powder spraying process onto the surface of silumin plates were applied, resulting in different coating thickness. The coating applied according to variant A was done with 12 passes, and its thickness was approximately 150 µm. The coating applied according to variant B was done with 20 passes, and its thickness was about 320 µm. The microstructures of these coatings are similar, consisting of wavy, alternately deposited phases of solid solutions with varying concentrations of elements, and fine spherical phases, irregularly dispersed carbides. A qualitative analysis of the distribution of microstructure components was performed based on surface mapping. Precipitates differing in their degree of grayness and shape were identified based on microanalysis of their chemical composition. The porosity assessment of coatings performed in five randomly selected areas amounts to an average of 9%. The applied coatings exhibit good adhesion to the substrate, as evidenced by the absence of delamination during scratching tests using a diamond Rockwell indenter loaded with a force of 10 N. The coating hardness averaged 1180HV0.2. The test results indicate the high quality of the WCCoCr coatings, regardless of their thickness.References
[1] Sokołowski, P., Łatka, L., Kozerski, S. & Ambroziak, A. (2015). Plasma spraying from slurries as an alternative to conventional powder plasma spraying. Spajanie materiałów konstrukcyjnych. 3(29), 28-31. (in Polish).
[2] Dudek, S., Gancarczyk, T. & Sosnowy, P. (2012). Application of thermal spraying on the example of a turbine engine. Welding Technology Review. 84(9), 9-13. DOI: https://doi.org/10.26628/wtr.v84i9.351. (in Polish).
[3] Bakan, E. & Vaßen, R. (2017). Ceramic top coats of plasma sprayed thermal barrier coatings: materials, processes, and properties. Journal of Thermal Spray Technology. 26, 992 1010. DOI: https://doi.org/10.1007/s11666-017-0597-7.
[4] Heimann, R. (2008). Plasma Spray coating: principles and applications (2nd ed.). German-Weinhem: Willey-VCH.
[5] Mróz, M. & Rąb, P. (2023). Evaluation of the possibility of applying thermal barrier coatings to AlSi7Mg alloy castings. Archives of Foundry Engineering. 23(3), 104-109. DOI: 10.24425/afe.2023.146668.
[6] Pierce, D., Haynes, A., Hughes, J., Graves, R., Maziasz, P., Muraligharan, G., Shyam, A., Wang, B., England, R. & Daniel, C. (2018) High temperature materials for heavy duty diesel engines: historical and future trends. Progress in Materials Science. 103, 109-179. DOI: 10.1016/j.pmatsci.2018.10.004.
[7] Tan, L.G., Li, G.L., Tao, C. & Feng, P.F. (2022). Study on fatigue life prediction of thermal barrier coatings for high power engine pistons. Engineering Failure Analysis. 138, 106335. DOI: https://doi.org/10.1016/j.engfailanal.2022.106335.
[8] Padture, N.P., Gell, M. & Jordan, E.H. (2002). Thermal barrier coatings for gas-turbine engine applications. Science. 296(5566), 280-284. DOI: 10.1126/science.1068609.
[9] de Goes, W.U., Markocsan, N., Gupta, M., Vassen, R., Matsushita, T. & Illkova, K. (2020). Thermal barrier coatings with novel architectures for diesel engine applications. Surface and Coatings Technology. 396, 125950. DOI: 10.1016/j.surfcoat.2020.125950.
[10] Uczak de Goes, W., Somhorst, J., Markocsan, N., Gupta, M. & Illkova, K. (2019). Suspension plasma-sprayed thermal barrier coatings for light-duty diesel engines. Journal of Thermal Spray Technology. 28, 1674-1687. https://doi.org/10.1007/s11666-019-00923-8.
[11] Opiekun, Z. (2014). Mechanical properties of the thermal barrier coatings made of cobalt alloy MAR-M509. In M. Aliofkhazraei (Eds.). Superalloys (331-335). Iran, Techeran. IntechOpen. DOI: 10.5772/61100.
[12] Reghu, V.R., Shankar, V. & Ramaswamy, P. (2018). Challenges in plasma spraying of 8% Y2O3-ZrO2 thermal barrier coatings on al alloy automotive piston and influence of vibration and thermal fatigue on coating characteristics. Materials Today: Proceedings. 5(11), 23927-23936. DOI: 10.1016/j.matpr.2018.10.185.
[13] Reghu, V.R., Lobo, K., Basha, A., Tilleti, P., Shankar, V. & Ramaswamy, P. (2019). Protection offered by thermal barrier coatings to Al-Si alloys at high temperatures - A microstructural investigation. Materials Today: Proceedings. 19(2), 676-681. DOI: 10.1016/j.matpr.2019.07.752.
[14] Pulsford, J., Venturi, F., Pala, Z., Kamnis, S. & Hussain, T. (2019). Application of HVOF WC-Co-Cr coatings on the internal surface of small cylinders: Effect of internal diameter on the wear resistance. Wear. 432-433, 202965. DOI: 10.1016/j.wear.2019.202965.
[15] Jonda, E., Łatka L., Lont A., Gołombek K., Szala M. (2024). The effect of HVOF spray distance on solid particle erosion resistance of WC-based cermets bonded by Co, Co-Cr and Ni deposited on mg-alloy substrate. Advances in Science and Technology Research Journal. 18(2), 115-128. DOI: https://doi.org/10.12913/22998624/184025.
[16] Akkaş M. (2020). The mechanical and corrosion properties of WCCo-Al coatings formed on AA2024 using the HVOF method. Material Research Express. 7(7), 076515, 1-18. DOI 10.1088/2053-1591/ab9fba.
