| Autor: |
Kiilakoski, J. (Jarkko), Puranen, J. (Jouni), Heinonen, E. (Esa), Koivuluoto, H. (Heli), Vuoristo, P. (Petri) |
| Jazyk: |
angličtina |
| Rok vydání: |
2019 |
| Předmět: |
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| Popis: |
Thermal spraying using liquid feedstock can produce coatings with very fine microstructures either by utilizing submicron particles in the form of a suspension or through in situ synthesis leading, for example, to improved tribological properties. The focus of this work was to obtain a bimodal microstructure by using simultaneous hybrid powder-precursor HVOF spraying, where nanoscale features from liquid feedstock could be combined with the robustness and efficiency of spraying with powder feedstock. The nanostructure was achieved from YSZ and ZrO₂ solution-precursors, and a conventional Al₂O₃ spray powder was responsible for the structural features in the micron scale. The microstructures of the coatings revealed some clusters of unmelted nanosized YSZ/ZrO₂ embedded in a lamellar matrix of Al₂O₃. The phase compositions consisted of γ- and α-Al₂O₃ and cubic, tetragonal and monoclinic ZrO₂. Additionally, some alloying of the constituents was found. The mechanical strength of the coatings was not optimal due to the excessive amount of the nanostructured YSZ/ZrO₂ addition. An amount of 10 vol.% or 7 wt.% 8YSZ was estimated to result in a more desired mixing of constituents that would lead to an optimized coating architecture. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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