Inspection device using electromagnetic induction and method therefor.

摘要

An electromotive induction current which is detected by an induction coil (30b) placed in an electromagnetic field generated by applying an alternating current to an exciting coil (30a) distinctively changes with the frequency of the applied alternating current in accordance with the conditions of an object (S) placed in the electromagnetic field. By analyzing the change in amplitude and/or frequency phase of the electromotive induction current, the physical properties, size and relative position of the object and internal defects such as a crack and pin hole in the object can be measured precisely. <IMAGE>