Abstract: A thermal barrier coating material contains a compound X that is a cation-deficient-type defective perovskite complex oxide. Unit cells of the compound X each include six oxygen atoms and has a structure in which two octahedrons sharing one oxygen atom are aligned. In the compound X, central axes of two octahedrons that belong to adjacent unit cells, respectively, and are adjacent to each other are inclined relative to each other. A plurality of sets of the two octahedrons that belong to the adjacent unit cells, respectively, and are adjacent to each other are arranged to form a periodic structure in which octahedrons having different inclinations are alternately arranged, and the compound X has a boundary surface at which a periodicity of the periodic structure changes, in a crystal structure thereof.

Abstract: A thermal barrier coating includes: a metal bonding layer made of an alloy containing Al; a thermal barrier layer; and an intermediate layer provided between the metal bonding layer and the thermal barrier layer. The thermal barrier layer contains a compound represented by the following general formula (1), LnxTayHfzO(3x+5y+4z)/2 (1) (wherein Ln is an atom of one element selected from among rare earth elements, x is 0 to 1.0, y is 0.8 to 3.0, and z is 0 to 7.0). The intermediate layer contains at least one layer selected from among the following (A) to (C): (A) a layer containing hafnium oxide (HfO2) as a main component; (B) a layer containing, as a main component, a compound consisting of tantalum (Ta), hafnium (Hf), and oxygen (O); and (C) a layer containing, as a main component, a compound consisting of a rare earth element, tantalum (Ta), hafnium (Hf), and oxygen (O).