Guided Wave Inspection of Railway Tracks: A Review of Electro Magnetic Acoustic Transducer Techniques

Indian Railway has expanded its track to approximately 115, 000 kms reaching to every nook and corner of the country. Both the passenger and freight traffic are continuously increasing along with increase in axle loads, warranting for more accurate and faster tracks inspection techniques. Present work is a review on Guided Wave Inspection Techniques using Electro-Magnetic Acoustic Transducer (EMAT) for railway track. Guided wave inspection potentially enables a large area of structure to be tested from a single transducer position, so avoiding the time-consuming scanning required by conventional ultrasonic or eddy current methods. However, full utilization of EMAT techniques warrants tackling of the issues like difficulty of controlling the different possible modes and propagation directions. It is therefore important for research in this field to counterbalance the benefits offered by the multiple possible modes, with the complexities that the presence of so many modes can produce.