Ultrasonic surface wave propagation and interaction with surface defects on rail track head
Ultrasonic surface wave propagation and interaction with surface defects on rail track head
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DOI：
10.1016/j.ndteint.2007.01.008
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发表时间：
2007-09-01
影响因子：
4.2
通讯作者：
Jian, X.
中科院分区：
文献类型：
--
作者：
Fan, Y.;Dixon, S.;Jian, X.
电磁声换能器(EMAT)是一种非接触式超声换能器，能够在金属样品上产生宽带超声表面波。研制了一套基于实验室的激光EMAT系统，用于观察超声表面波的传播及其与试件轨头表面破损缺陷的相互作用。产生频率在大约50至500 kHz之间的表面波的宽带EMAT被用来沿样品的长度在轨头表面上传播超声波。用稳定的迈克尔逊干涉仪测量面波的离面位移。使用该技术重建了样品表面随时间变化的超声表面波的完整图像，具有极高的空间和时间分辨率。尽管轨头是弯曲的，但通过与使用相同技术在平板样品上观察到的结果进行直接比较，发现沿轨道传播的超声波表面波具有与瑞利波相似的特性。(C)2007爱思唯尔有限公司。保留所有权利。
Electromagnetic acoustic transducers (EMATs) are non-contact ultrasonic transducers capable of generating wide band ultrasonic surface waves on metallic samples. A lab-based laser-EMAT system has been developed to observe the ultrasonic surface wave propagation and interaction with surface breaking defects on the sample rail head surface. A wide band EMAT generating surface waves with a frequency content between approximately 50 and 500 kHz is used to propagate ultrasonic waves on the surface of a rail head down the length of the sample. A stabilised Michelson interferometer is used to measure the out-of-plane displacement of the surface wave. A complete picture of the ultrasonic surface wave on the sample surface over time is reconstructed using this technique, with exceptionally high spatial and temporal resolution. Despite the curvature of the rail head, the ultrasonic surface wave propagating down the rail is found to have similar properties to Rayleigh waves by direct comparison to those observed on flat samples using the same technique. (c) 2007 Elsevier Ltd. All rights reserved.