LAUSR

In this article, the contributions are to further study and verify a bulk-wave electromagnetic acoustic transducer (EMAT) for the transverse crack detection of rail base and to propose an auxiliary method for achieving efficient detection. There is no verification for rail treated as a plate in the previous publication. For the verification, the wedge-like rail base is reasonably simplified into the front view and the side view to replace the 3-D finite-element model (FEM) simulation. In addition, the experiment to detect an artificial transverse crack of the standard rail specimen is carried out to verify the treatment of the wedge-like rail base. Both simulation and experimental results demonstrate that the wedge-like rail base can be inspected as a steel plate using a spiral-coil EMAT, but the only time of flight is hard to detect the transverse crack of the wedge-like rail base due to low SNR. For solving the problem of low SNR, this article proposes an auxiliary method of watching for the disturbances of the back-wall echo. Also, the limit condition of the auxiliary method is analyzed for practical applications.