Effects of Process Parameters on the Zirconia Coating Prepared by Sol-Gel and Electrodeposition Process

Abstract

In this study, sol-gel process followed by electrodeposition process was used to prepare a ZrO2 coating on the Fe–Al alloy layer. The sol-gel process is prone to produce pores. We studied the effect of pulling speed on the ZrO2 coating. The electrodeposition process was further used to densify the coating. The deposition time had a significant effect on the porosity. The surface and cross-sectional morphology of the coating was observed by scanning electron microscope, and the phase structure was detected by X-ray diffraction. The results revealed that the ZrO2 coating when being pulled at 120 mm/min had the minimum porosity of 6.48%. Almost no pores were found on the surface after three times of 6-min deposition. The thickness of the ZrO2 coating after deposition for 6 min was about 13 μm. The internal Fe–Al alloy bond coat contained FeAl3, Fe2Al5, FeAl and Fe3Al phases, and the external ZrO2 coating contained t-ZrO2 and m-ZrO2 phases.