Microstructure and oxidation-resistant of ZrO₂/Ni coatings applied by high-speed jet electroplating

摘要

ZrO₂/Ni composite coatings with different contents of ZrO₂ particles were deposited on superalloy K17 substrate using high-speed jet electroplating process. The microhardness and microstructure of composite coatings were studied. The oxidation kinetic curves of uncoated and coated K17 alloys were obtained. The results indicated that ZrO₂/Ni composite coatings exhibit higher microhardness than that of pure nickel coatings under the same high-speed jet electrodeposition conditions. ZrO₂/Ni composite coatings exposure to air at 1000 °C for 5 h formed scale containing NiO and Cr₂O₃; after exposure to air at 1000 °C for 100 h the scale was comprised NiO, NiCr₂O₄, and Cr₂O₃. The formation of Cr₂O₃ scales on the ZrO₂/Ni composite coating directly improved the oxidation resistance of superalloy K17.