An experimental study of EMAT ultrasonic surface waves modes in railhead

Issue title: Selected Papers from the 14th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2009), Part II

Article type: Research Article

Authors: Lu, Chao^{a; *} | Men, Ping^a | Li, Lianxiu^b

Affiliations: [a] Key Laboratory of Nondestructive testing, Ministry of Education, Nanchang Hangkong University, 330063, Jiangxi Nanchang, P.R. China | [b] Metal and Chemistry Research Institute, China Academy of Railway Science, 100081, Beijing, P.R. China

Correspondence: [*] Corresponding author. Tel.: +86 0791 3953491; E-mail: [email protected]

Abstract: A lab-based laser-EMAT (Electromagnetic acoustic transducers) system has been developed to observe the ultrasonic surface wave propagation and interaction with surface breaking defects on the sample rail head surface. The frequency-wavenumber dispersion curves of the dominant surface wave modes were determined using 2D-FFT method based on the measurements of the out-of-plane displacement of the surface wave. A complete picture of the ultrasonic surface wave on the sample surface over time was reconstructed with exceptionally high spatial and temporal resolution. Despite the curvature of the rail head, the ultrasonic surface guided 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.

Keywords: EMAT, ultrasonc surface waves, 2D-FFT, rail

DOI: 10.3233/JAE-2010-1229

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 3-4, pp. 1127-1133, 2010