| 摘要 |
[PROBLEMS] To provide a composite structure which comprises a base and a structure made of yttrium oxide formed on the base and having improved mechanical strength. [MEANS FOR SOLVING PROBLEMS] The composite structure comprises a base and a structure made of yttrium oxide formed on a surface of the base. The structure made of yttrium oxide comprises polycrystalline yttrium oxide as the main component. Substantially no grain boundary layers made of a vitreous substance exist at the interface between the crystals constituting the structure and the polycrystalline yttrium oxide has crystal structures comprising a mixture of a cubic system and a monoclinic system. Due to the constitution, the structure made of yttrium oxide formed on a base can have a higher hardness than an yttrium oxide sinter. |
