Lanthanum zirconate (La_2Zr_2O_7) is one of the proposed next generation thermal barrier coating materials with a low thermal conductivity and a superior high temperature stability. In this study the La_2Zr_2O_7 and conventional 8wt% yttria stabilized zirconia (8YSZ) coatings were deposited using a plasma spray technique. The single and double-layered coating architectures were designed for evaluation. Coating's thermal and mechanical properties were characterized. Thermal shock tests were implemented using jet engine thermal shock (JETS) tests. Although confirmed with a lower thermal conductivity in this test, La_2Zr_2O_7 coatings present lower bond cap tensile strength and poor erosion resistance comparing to conventional 8YSZ coatings. The double-layered structure, with a La_2Zr_2O_7 coating on the top of a porous 8YSZ sublayer coating, has a better thermal shock performance than either single layer La_2Zr_2O_7 coatings or double-layered structure with a dense 8YSZ sublayer.
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