Magnetostrictive steady-state guided wave testing technique for defect detection in pipes

摘要

A new magnetostrictive steady-state guided wave technique (MST) based on long time excitation is proposed for Nondestructive Evaluation (NDE) and Structural Health Monitoring (SHM) in pipes. Due to the non-contact inspection, it has no need to consider the influence on vibration state while moving sensors along the pipe. Both simulation and experimental results show that the vibration state is associated with specific propagating guided wave mode and the defect causes an obvious change of the steady-state stage vibration amplitude at certain specific positions along the pipe, which can be utilized for defect location. Moreover, the precision of defect location increases with the excitation frequency increasing.