Abstract
Plasma-sprayed aluminum oxide (AI2O3) and chromium oxide (Cr2O3) coatings were sealed by aluminum phosphates. Phosphates were formed throughout the coating, down to the substrate, and were verified by scanning electron microscopy and hardness measurements. The sealing increased the hardness of the coatings by 200 to 300 Vickers hardness (HV) units. Abrasion and erosion wear resistances were increased by the sealing treatment. Sealing also substantially closed the open porosity, as shown in electro-chemical corrosion tests. The sealed structures had good resistance against corrosion during 30 days of immersion in both acidic and alkaline solutions with pH values from 0 to 10. No decrease in abrasion wear resistance was observed after immersion.
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Leivo, E., Vippola, M.S., Sorsa, P.P.A. et al. Wear and corrosion properties of plasma sprayed AI2O3 and Cr2O3 coatings sealed by aluminum phosphates. J Therm Spray Tech 6, 205–210 (1997). https://doi.org/10.1007/s11666-997-0014-8
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DOI: https://doi.org/10.1007/s11666-997-0014-8