A magnetostrictive sensor for structural health monitoring in a non-ferromagnetic plate

摘要

In this work,the development of a magnetostrictive sensor for generating and detecting guided waves in a non-ferromagnetic plate is described.From the theory and experiment it can be proven that the sensor can generate non-dispersive horizontal shear(SH0)wave mode for structural health monitoring.The sensor system consists of a nickel strip,a couple of Nd-Fe-B permanent magnets,C-shaped cores,and the figure-of-eight coil wound on it.The incident wave propagates in the plate and is reflected from the plate boundaries.Since the time of the arrival can be determined from the reflected wave signal through signal processing,the velocity of the wave can be calculated.Comparing the calculated velocity with the theoretical velocity,the mode of the wave can be identified with a priori knowledge of group velocity of the plate.The sensor shows its promise in applying in SHM and nondestructive evaluation(NDE).