Abstrakt: |
The paper summarizes the results of research concerned with optimization of the eddy current probe of the parametric type used for surface defects detection. It is shown that the choice of eddy current probe diameter significantly depends on the smallest length of cracks needed to be detected. In particular, it was determined that to detect a crack longer than 2 mm, it is optimal to use an eddy current probe with windings mounted on the 1.2 mm diameter ferrite core. To detect shorter cracks longer than 1 mm, it is necessary to use an eddy current probe with windings on the 0.75 mm diameter ferrite core. The influence of ferrite core parameters (length, magnetic permeability, and offset of winding from the ferrite core end) on the efficiency of parametric type eddy current probes is analyzed. The results obtained should be used for eddy current probe optimization. The conditions of separation of defect and lift-off influence are analyzed by interpretation of signals in the complex plane, and the possibility of their separation for the developed eddy current probes for all nonmagnetic structural alloys is shown. The design of a parametric type eddy current probe makes it possible to increase their quality factor more than twice. The optimal choice of the cable for connection of an eddy current probe and flaw detector is considered. The optimized parametric eddy current probes were tested. The high sensitivity of the developed probe to short cracks longer than 2 mm with reliable separation of the defect and lift-off influence was shown. [ABSTRACT FROM AUTHOR] |