Abstract
In this paper, we propose a new method for estimating the position and inclination angle of a reverse-side crack in a steel plate. To detect a crack existing on a side of steel plate opposite to a sensor, we have devoloped a new rotational magnetic flux sensor with a three-axis search coil centered between two pairs of exciting coils. It can measure the magnitude and phase of the magnetic flux caused by a crack in a steel plate. Using steel plates with a crack machined in the center, we investigated the relationship between the position and inclination angle of the crack and the output signals obtained by the three-axis search coil. The experimental results show that the sensor can detect the position and inclination angle of the reverse-side crack clearly.
