Induction Thermography for Rail Nondestructive Testing under Speed Effect

With the development of high-speed and heavy haul of railway, flat and spalling are becoming serious in wheel tread and rail surface, it is a huge threat to the safety of passengers. A major concern in railway quality is the occurrence of micro-crack in the near surface on the railhead because of the rolling contact fatigue (RCF). It is of great significance to detect the RCF crack with high accuracy. This paper investigates micro-crack and Uolling contact fatigues (RCF) detection on the railhead using induction thermography under speed effect. A thermal imaging detection mechanism of a moving mode is studied. Both simulation of rail cracks and experiment of a rotating disk are conducted. The blurred image formation is explained and the deblurring method is proposed. Different inductive sensing architecture are compared and discussed.