钢轨轨头浅表面缺陷的空气耦合超声导波检测

摘要

Due to some shortcomings,the usual piezoelectric ultrasonic,eddy current,magnetic flux leakage, machine vision and other surface inspection methods cannot meet the rail head shallow surface defects detection requirements.In this paper,the air-coupled ultrasonic Rayleigh like wave detection method is used to evaluate the shallow surface defects of the rail head by using the change of the amplitude of the echo signal at different frequencies and different defect depths.Through the simulation and experimental research on the air coupled ultrasonic guided wave detection process,the feasibility and reliability of the detection are proved.%针对常规检测方法如压电超声、涡流、漏磁及机器视觉等表面检测方法均无法对钢轨轨头浅表面缺陷进行检测的问题,采用空气耦合超声类瑞利波检测方法,利用回波信号在不同频率、不同缺陷深度下幅值的变化来评估钢轨轨头的浅表面缺陷.通过对空气耦合超声导波检测过程的仿真和试验,证明了该检测方法的可行性和可靠性.