This study integrates metal 3D printing technology

optical fiber metallization

and laser welding preparation – encapsulation processes to design a high-temperature

large-strain optical fiber sensor with low stiffness and a wide measurement range. The aim is to address the challenge of monitoring thermal and mechanical parameters in aeroengine turbine blades. The designed sensor employs a hybrid demodulation method based on fiber Bragg grating (FBG) wavelength and light intensity

enabling precise measurement of temperature and strain. Through theoretical modeling

finite element simulation

and structural optimization of a grooved “8”-shaped spring substrate

the sensor’s reaction force on the measured structure is reduced to 167 N/ε. Experimental results demonstrate that the sensor can achieve a large-range strain measurement of 37520 με

with a temperature linearity of 0.9878 within the range of room temperature to 500 ℃. Additionally

the sensor exhibits excellent temperature-strain decoupling performance

with a maximum decoupling error of less than 8%. These outstanding characteristics indicate that the designed sensor has promising application prospects for high-temperature strain monitoring in aero-engine turbine blades.