To prevent peeling of thermal barrier coating material even in the case of high temperature sintering by providing, along the edge, grooves to the surface of a thermal barrier coating material applied to the surface of a base metal.

The inside peripheral surface of a base metal 13 of, e.g. a casing 11 of a gas turbine engine is coated with a thermal barrier coating material 15 by thermal spraying. Further, grooves 16, 16 of V-shaped sectional form are parallelly formed, along the edge, in the surface of the thermal barrier coating material 15 by means of a cutter, a laser cutter, etc. Then, the coating material 15 is heated together with the base metal 13 under the service condition of engine and sintered, by which the inside peripheral surface of the base metal 13 can be coated with the coating material 15. Even if the coating material 15 shrinks when sintered, the shrinkage force applied to the coating material 15 on the end side to the grooves 16 can be divided by the grooves 16 and reduced because the continuity of the surface of the coating material 15 is divided by the grooves 16.