Based on energy dissipation investigation of preparation and toughening mechanism of continuous transition coating

Abstract

The plasticity and toughness of metals can absorb a large amount of energy. In this study, we focused on the preparation of the continuous transition coating of yttria-stabilized zirconia (YSZ) and CoNiCrAlY via the atmospheric plasma spraying (APS) method. The external force produced by Vickers hardness initiated the growth of cracks. Thus, the energy dissipation of the coatings was studied. The results confirmed that the continuous transition structure exhibits a hardness gradient change and excellent energy dissipation. The results indicated that the hardness curve of the continuous transition coating with slope kCTC = 5.728 compared to the double-layer coating curves with slope kDLC = 18.75 can alleviate the hardness differences between metals and ceramics. In contrast, CoNiCrAlY in the continuous transition zone dissipated energy through deformation, avoiding the failure of the coating caused by the large-scale fracture of the 8YSZ splats. Its energy dissipation increased with the gradient of the metal content in the continuous transition zone in the following order: ΔJsa=0J < ΔJsb=6.0072×10−9J<ΔJsc=7.3778×10−9J.