抄録
In nuclear power plants, existence of a flaw, the size of which does not have a problem on safety, is permitted. Therefore, a method for exact sizing of flaws is expected. Electromagnetic acoustic transducers (EMATs) can transmit and detect ultrasonic waves in a conductive specimen without any contact. This process can be described mathematically. It suggests the possibility of quantitative nondestructive evaluation using EMATs. As we examined, using these EMATs, specimens which have a crack, we confirmed the effect of crack depth is appeared on the peak value of S wave of a received signal. For this reason, it was shown that the position and the depth of a flaw may be able to be specified by EMATs.
