Particle erosion behavior of La2(ZrxCe1-x)2O7/YSZ double ceramic layers TBCs deposited by electron beam-physical vapor deposition

La₂(Zr_xCe_1-x)₂O₇/YSZ (LZC/YSZ) double ceramic layers (DCL) thermal barrier coatings (TBCs) have attracted extensive attentions due to their low thermal conductivity and good thermal stability. Particle erosion of DCL TBCs is one of the typical degradation patterns. Here, LZC/YSZ DCL TBCs samples deposited by electron beam-physical vapor deposition (EB-PVD) underwent solid particle erosion test for different time. Characterization of microstructure evolution is implemented using correlative methods, which links together the observations and analysis from X-ray diffraction (XRD), scanning electron microscopy (SEM) and white light scanning interferometry (WLSI). The erosion rates for LZC/YSZ DCL TBCs were determined after exposure to varying durations of erosion. During the initial erosion stages, the predominant degradation mechanism involved the removal of ceramic material. This was attributed to the compaction and cracking of the near-surface columns, causing a progressive thinning of the coating in a layer-by-layer manner. This pattern of degradation also occurred at the LZC/YSZ interface, indicating a relatively good adhesive bond between the LZC and YSZ layers. In the later stages of erosion, the formation of deep cracks, erosion craters, and the emergence of horizontal cracks within the bottom of YSZ layer contributed to block spalling, consequently increasing the erosion rate.