Thermoelectric properties of ceramic thin film thermocouples
Date of Original Version
Thin film ceramic thermocouples are being developed to assess temperatures beyond 1400°C in the hot sections of gas turbine engines. Several promising ceramic materials were systematically investigated as thermoelements including (ITO), alumina doped zinc oxide (ZnO) and a NiCrCoAlY/alumina nanocomposite. These ceramic thermoelements were initially tested relative to a platinum reference electrode and the resulting thermoelectric properties were evaluated. Bi-ceramic junctions comprised of the most stable and responsive ceramic thermoelements, i.e. those thermoelements with the largest and most stable Seebeck coefficients relative to platinum, were fabricated and tested. Bi-ceramic junctions based on nitrogen-doped ITO:oxygen-doped ITO exhibited excellent high temperature stability and reproducibility, however, this thermocouple pair had a relatively low Seebeck coefficient (6μV/°C). Alumina doped ZnO:ITO thermocouples generated a very large electromotive force at low temperatures but lacked high temperature stability. When nitrogen-doped ITO was combined with a NiCoCrAlY/alumina nanocomposite, a very large and stable Seebeck coefficient (375 μV/°C) was realized. Ceramic thermocouples based on these materials were demonstrated at temperatures up to 1200°C and the potential for temperature sensors and energy harvesting for the production of electrical energy at a remote location with minimal processing is discussed. Copyright 2006 ISA. All rights reserved.
Proceedings of the International Instrumentation Symposium
Gregory, Otto J., Elke Busch, and Gustave C. Fralick. "Thermoelectric properties of ceramic thin film thermocouples." Proceedings of the International Instrumentation Symposium 467, (2006): 234-248. https://digitalcommons.uri.edu/che_facpubs/175