3D printing of high-temperature thick film platinum resistance temperature detector array

Dynamic high-temperature field measurements have garnered substantial interest for various promising applications, such as the health monitoring of aviation components. 3D printing offers unprecedented opportunities for the development of curved structure-function integrated sensors. However, most current resistance temperature detector (RTD) arrays based on 3D printing technology work well only within a narrow temperature range. Their application at high temperatures remains a significant challenge because of the lack of efficient manufacturing processes. Herein, a high-temperature thick film platinum (Pt) RTD array is presented based on 3D printing technology, suitable for high-temperature field measurement sensing applications at 50−800 °C. Three stages of Pt film sintering were revealed through the analysis of the microstructure, phase composition, and electrical properties during the sintering process. Compared to sputtered films, printed Pt films, which are confirmed to contain glass powder, exhibit excellent anti-aggregation and high-temperature properties. The resulting Pt RTD array shows outstanding stability (drift rate of 0.07%/h at 800 °C), high accuracy (0.75% full-scale), and can realize temperature gradient monitoring of a two-dimensional temperature field. The potential applications of the Pt RTD array, including bolt and rocket engine tester exhaust flame temperature monitoring, were demonstrated. This study paves the way for printing RTD arrays directly on curved parts.