Conformal Printed High-Temperature Platinum-Rhodium Resistance Temperature Detector for Ceramic Bolts

The operation temperature detection of high-temperature hot-end components in aerospace and other fields is of great significance for operational safety; however, the higher working temperature and noninvasive in situ measurement of temperature detectors currently face significant challenges. Here, the platinum-rhodium (PtRh) conformal resistance temperature detector (CRTD) was proposed, the structure and preparation process was elaborated, and the aging sintering process of the film was explored to form a stable conductive network with high porosity. The dense surface and cross-sectional characteristics of the film were demonstrated, the lattice characteristic of PtRh was demonstrated, and the composition and valence states of the elements were characterized in detail. The high-temperature testing system was built, and the test results showed that the developed PtRh CRTD could achieve dynamic temperature detection at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1200~^{\circ }$ </tex-math></inline-formula>C, with a linear fitting goodness of 0.99834. The resistance drift rate of the 31 h high-temperature durability test was 1.11%/h, and the maximum full-scale error was 1.58%FS. Furthermore, the PtRh high-temperature conformal ceramic bolt was prepared and subjected to thermal shock testing. The results showed that it more accurately reflects the temperature of the structural component itself than the discrete surface mount temperature measurement method, providing a feasible solution for in situ detection of complex curved high-temperature hot-end components.