| 摘要 |
1,156,383. Thermocouples. BRISTOL AEROJET Ltd. 5 Jan., 1968 [10 Jan., 1967], No. 1361/67. Heading H1K. The hot junction of a thermocouple is formed by welding the metal limbs of the couple to an intermediate member having a melting point above 2000‹ C. but lower than that of either limb. A preferred method involves resistance welding tungsten-rhenium wires containing 5 and 26% by weight of rhenium respectively to one face of a disc-shaped tantalum shim and then directing an electron beam on the other face of the shim to melt it about the wires. Finally ceramic leads are threaded on the wires and the assembly placed in a tantalum tube. The junction at one end of the tube is surrounded with powdered ceramic and after the end has been sealed by welding in a plug the tube is swaged to compact the ceramic. An alternative metal for the intermediate member is niobium. |
