In this research, a uniform eddy current multi-probe to apply to the complex structure and inspect the cracks at high-speed data ac quisition was developed. Pick-up coils of the developed probe were arranged on a flexible printed circuit board. It was confirmed t hat the SCC (stress corrosion cracking) of real flaw was able to be detected with developed uniform eddy current multi-probe by usin g the ferrite core for the exciting coil and considering the impedance matching of the exciting coil and the flaw ...
英字タイトル:
Development of uniform eddy current multi-probe and characteristic evaluation of SCC detection

In yoke method magnetic-particle testing, it is necessary to perform the testing at least two times by changing the direction of magnetization. In a rotating field type magnetizer using a three-phase al ternating current (AC), any directional flaw can be detected by a single testing. In this research, the distributions of the rotating magnetic flux density were evaluated by measuring this density using Hall elements (in three directions) and by numerical analysis. The distributions of the magnetic flux den...
英字タイトル:
Evaluation of generated field in magnetic-particle testing using rotating field

In eddy current testing (ECT), the permeability distribution of the steel materials affects inspection results and the signal-to-noise (S/N) ratio decreases. Therefore, magnetizing the materials is required to reduce the magnetic noise. In this research, the spring steel materials that have artificial microcracks were magnetized and inspected to evaluate detection performance of a developed ECT probe. It was confirmed that the probe is able to detect the 40 ?m depth crack with the S/N ratio of 3 or more. I...
英字タイトル:
Flaw detection for microcrack and crack shape estimation with magnetic saturation ECT

Mechanical parts, plants and cross-linkages inspected with magnetic-particle testing (MT) are typically complex 3D shapes. In complex 3D shape portions, because a magnetizer often cannot be configured to inspection portions and the test object cannot be appropriately magnetized, there is a possibility of overlooking a crack in such an instance. Thus, MT system development that was successfully able to detect omnidirectional cracks in 3D shape portions was considered in this study’s trials. Two multi-coil ty...
英字タイトル:
Development of magnetization system for magnetic particle testing in all surfaces of 3D shape test object