Research on Ultrasonic Stress Precision Measurement Method

Accurate measurement of stress in key components is a necessary guarantee for improving the comprehensive performance and operational safety of high-end equipment. In order to improve the accuracy of stress measurement, this paper proposes an ultrasonic stress precision measurement method that considers temperature changes. This method adds a feedback transducer between the ultrasonic transmission and reception transducers, which receives longitudinal wave signals containing temperature and stress change information through the feedback transducer. The temperature and stress information were calculated based on the longitudinal wave acoustic time difference (ultrasonic propagation time difference) <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta t_{F}$</tex> and critical refracted longitudinal wave (LCR wave) acoustic time difference <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta t_{R}$</tex>, thus separating the stress measurement error caused by temperature changes. The research results indicate that the maximum stress measurement error of this method is 2.302 MPa, which effectively improving the accuracy of stress measurement.