| 摘要 |
PURPOSE:To accurately control each dimension ratio, by selecting such a temperature and oxygen partial pressure in directly conjoining single-crystal ferrite and polycrystalline ferrite to each other that a higher oxidizing condition is set than in the production of each ferrite. CONSTITUTION:When single-crystal ferrite and polycrystalline ferrite are conjoined to each other under pressure in a hot working range, the crystal grains of the polycrystalline ferrite are annexed to the single-crystal portion so that the crystal grains become a part of the single crystal. The thickness of the grown layer is not uniform on the boundary surface of the conjoining. The velocity of the annexation is greatly affected by the temperature and oxygen partial pressure of the conjoining, namely, the single-crystal ferrite and the polycrystalline ferrite are greatly affected by the conjoining heat treatment condition such as an oxidizing condition or a reducing condition. If a higher oxidizing condition is selected than in the production of each ferrite, the grown layer of the single-crystal ferrite is thin and a conjoined piece consisting of both ferrite regions is produced with a prescribed dimensional accuracy. |
