| 摘要 |
A protective sheath for a temperature sensing device for use in determining the temperature of molten metals. The temperature sensing device, such as a thermocouple, is encased in a molybdenum tube which is coated with successive porous layers of molybdenum, a plurality of layers of Al2O3-Cr2O3-Mo in a decreasing concentration of Mo in proceeding from the inner to the outer layers, and a layer of substantially pure Al2O3-Cr2O3. The Al2O3-Cr2O3 layer may be covered with an outer coating of a material, such as boron nitride, to protect the Al2O3-Cr2O3 layer from attack by slag. Alternating layers of Al2O3-Cr2O3 and boron nitride may be applied as outermost sacrificial layers. |
