Deposition of hybrid plasma-sprayed coatings employing both dry powder and liquid feedstocks enables preparation of innovative coating architectures. Using this technique, miniature domains of additional (secondary) material may be introduced via the liquid feedstock route into the more conventional powder-deposited coating, providing potential benefits for the coating functionality. In this contribution, we have explored the tribological properties of hybrid coatings sprayed from alumina powder with additions of chromia (Cr_2O_3), zirconia (ZrO_2), yttria-stabilized zirconia (YSZ), and titania (TiO_2) delivered from liquid feedstocks. The coatings were subjected to dry sliding wear testing and a subsequent analysis of the wear tracks to determine their wear resistance and coefficient of friction, as well as a qualitative assessment of the wear mechanisms. The hybrid coating doped with the chromia addition matched the remarkable wear resistance of highly-dense suspension-sprayed coatings. This is a significant result, especially when considering the order of magnitude better production efficiency of the hybrid coatings.
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