Accounting for Temperature Influence in Non-destructive Measurements of Applied and Residual Stresses by Ultrasonic  Method

Understanding the impact of temperature on ultrasonic velocity in solids is crucial for accurately assessing residual stresses (RS). A methodology and equipment, UltraMARS™, were developed for non-destructive stress measurement using ultrasound that was used successfully in measuring RS in welded structures . We studied changes in longitudinal and transverse ultrasound velocities in steel and aluminum samples across temperatures ranging from 10°C to 50°C. We incorporated a technique in the UltraMARS™ system that takes into account the effects of temperature on the measurement of uniaxial and biaxial residual stresses measured in stress-free points on the specimen. From the conducted experiments and available information in the literature, it can be suggested that the temperature does not affect the residual stress values in average through-thickness measurements.