Abstract
Several options have been identified that could further enhance the lifetime and reliability of INL-developed thermocouples for in-pile testing, allowing their use in higher temperature applications (up to at least 1700℃ (3092^oF)). A joint University of Idaho (UI) and INL University Nuclear Energy Research Initiative (UNERI) is underway to investigate these options and, ultimately, provide recommendations for an enhanced thermocouple design. This paper presents preliminary results from this UI/INL effort. Results are reported from tests completed to evaluate the ductility, temperature resolution, transient response, and stability of thermocouples made from non-commercially available alloys of molybdenum and niobium. In addition, this paper reports preliminary insights gained by comparing the performance of thermocouples fabricated with various diameters.
