| 摘要 |
PURPOSE:To obtain the title member which is excellent in durability at the time when it is used at a high temperature by installing light transmissive single crystal alumina in an opening part of a ceramic member which becomes a light shielding material. CONSTITUTION:Single crystal alumina 2 is worked to a little smaller dimension than the inside peripheral diameter of an alumina cylindrical body 1. It is set to an inside peripheral part 3 of a cylindrical body 1 so that the C axis of the single crystal alumina 2 coincides with the axial direction of the alumina cylindrical body 1. Thereafter, it is burned in a state that its state remains held. The single crystal alumina 2 is weak against compressive force from the direction vertical to its C axis, and strong against compressive force from the peripheral direction of the C axis. Accordingly, the C axis is allowed to coincide with the axial direction of the alumina cylindrical body 1 so that contraction pressure of the inside diameter of the cylindrical body at the time of burning is applied from the peripheral direction of the C axis of the single crystal alumina 2. Also, said body is formed so as to be endurable enough against contraction stress at the time of burning of the generating mold body 1. In such a way, the durability can be improved especially for the use at a high temperature. |
