Improvement of Experimental Method Aimed at Enhancing the Accuracy of Calibration Curves in Magnetostriction Measurement

This chapter delves into the improvement of experimental methods for enhancing the accuracy of calibration curves in magnetostriction measurement, a non-destructive technique for assessing internal stress in steel structures. The study focuses on the influence of loading history, including initial loading, unloading, and reloading, on the calibration curves of SS400 steel. It also explores the impact of different measurement intervals on residual stress distribution in welded T-beams using SMA400W steel. The research employs a portable magnetostriction device, which simplifies the measurement process by eliminating the need for a PC connection. Key findings include the observation that residual strain affects calibration curves during unloading and reloading, and that expanding the measurement interval from 20 mm to 40 mm can still provide useful insights into stress conditions. The study concludes that stress release after unloading minimizes the influence of loading history on calibration curves and that the magnetostriction method, combined with the shear difference method, can accurately estimate residual stress distribution. This research offers valuable practical applications for professionals in the field of structural health monitoring and stress analysis.