In situ temperature monitoring of curved high-temperature
components
in extreme environments is challenging for a variety of applications
in fields such as aero engines and gas turbines. Recently, extrusion-based
direct ink writing (DIW) has been utilized to fabricate platinum (Pt)
resistance temperature detectors (RTDs). However, the current Pt RTD
prepared by DIW technology suffers from a limited temperature range
and poor high-temperature stability. Here, DIW technology and yttria-stabilized
zirconia (YSZ)-modified precursor ceramic film packaging have been
used to build a Pt RTD with high-temperature resistance, small disturbance,
and high stability. The results indicate that the protective layer
formed by the liquid phase anchors the Pt particles and reduces the
agglomeration and volatilization of the Pt sensitive layer at high
temperature. Attributed to the SiCN/YSZ protective layer, the temperature
resistance curve of the Pt RTD in the range of 50–800 °C
has little deviation from the fitting curve, and the fitting correlation
coefficient is above 0.9999. Interestingly, the Pt RTD also has high
repeatability and stability. The high temperature resistance drift
rate is only 0.05%/h after 100 h of long-term testing at 800 °C
and can withstand butane flame up to ∼1300 °C without
damage. Moreover, the Pt RTD can be conformally deposited on the outer
ring of aerospace bearings by DIW technology and then realize on-site,
nondestructive, and real-time monitoring of bearing temperature. The
fabricated Pt RTD shows great potential for high-temperature applications,
and the novel technology proposed provides a feasible pathway for
temperature monitoring of aeroengine internal curved hot-end components.