Calculating the phase angle of the 1st signal which deforms the eddy current flaw detection probe and the lift off quantitative evaluation method and its

摘要

PROBLEM TO BE SOLVED: To enhance evaluation precision for a lift-off amount of an eddy current flaw detecting probe with respect to a curved face shape part.;SOLUTION: A signal generated in each coil is measured 2 when deforming the eddy current flaw detecting probe having a plurality of flexible coils, and a phase θ of the signal is evaluated 4. The signal generated in the each coil is measured 5 in every time when changing a distance between the eddy current flaw detecting probe and a flat face comprising a material same to that of an inspected object. A value of a phase angle component having θ+90° with respect to the signal detected in the measurement 5 is extracted 7 to prepare a data table of the distance corresponding to the value of the extracted component. Then, the eddy current flaw detecting probe is attached 9 to the inspected object in actual flaw detection inspection, a signal generated in the coil is measured 10 under this condition, a value of a phase angle component having θ+90° with respect to the signal detected in the measurement 10 is extracted 29, and the distance corresponding to the extracted 29 value is found from the data table to serve as an evaluation result 11 of the lift-off amount.;COPYRIGHT: (C)2007,JPO&INPIT