journal article·2012-08

Finite element modelling of closed cracks in eddy current testing

Anders Rosell, Gert Persson

Publisher page

Abstract

The eddy current inspection of small fatigue cracks in Ti-6AL-4V is evaluated in both a finite element model and experiments. The crack was created in a fatigue process and an eddy current measurement was carried out as the resulting crack was subjected to different levels of static load. The signal showed a strong dependency of the time between the creation of the fatigue crack and the eddy current measurement. This dependency is proposed to be related to oxides forming on the crack faces. The oxide is favourable for the detection of fatigue cracks. The narrow width of the fatigue crack is important to consider in eddy current inspection and as static loads are applied across the crack faces, electrical connections arise within the crack, which has a strong influence on the eddy current signal. Four different models of the contact behaviour were implemented within the finite element model. It is shown that the electrical connections that arise within small fatigue cracks, as well as the influence from the narrow opening as tensile loads are applied, can be predicted by a finite element model of the eddy current method.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Non-Destructive Testing Techniques · Ultrasonics and Acoustic Wave Propagation · Welding Techniques and Residual Stresses

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (24)

Show source-provided references
1. Eddy current probe response to open and closed surface flaws10.1007/BF00614993 ↗
2. Kurokawa M. Relationship between electric properties and width of cracks of inconel alloy. in: Proceedings of the 13th international conference on NDE in the nuclear and pressure vessel industries; 1995.
3. Effect of crack closure on eddy current signals
4. Discussion on the equivalent conductivity and resistance of stress corrosion cracks in eddy current simulations10.1016/j.ndteint.2008.09.007 ↗
5. Website. Picasso Project (picasso – improved reliability inspection of aeronautic structure through simulation supported pod); 2011a. .
6. A justification of eddy currents model for the maxwell equations10.1137/S0036139998348979 ↗
7. Bossavit · 1998
8. On the use of the magnetic vector potential in the finite element analysis of three-dimensional eddy current problems10.1109/20.34388 ↗
9. A comparison of the coulomb gauge and lorentz gauge magnetic vector potential formulations for 3d eddy current calculations10.1109/20.250658 ↗
10. Edge element formulations of eddy current problems10.1016/S0045-7825(98)00165-0 ↗
11. Magnetic vector potential and electric scalar potential in three-dimensional eddy current problem10.1109/TMAG.1982.1061856 ↗
12. Solving 3d eddy current problems using second order nodal and edge elements10.1109/20.877555 ↗
13. Bondeson · 2005
14. A new formulation of the magnetic vector potential method in 3-d multiply connected regions10.1109/20.43868 ↗
15. Review of advances in quantitative eddy current nondestructive evaluation10.1023/A:1021898520626 ↗
16. Alternative approaches to the numerical calculation of impedance10.1016/0308-9126(88)90381-1 ↗
17. International compumag society; 2011b. .
18. A benchmark problem for computation of δz in eddy-current nondestructive evaluation (nde)10.1007/BF00565775 ↗
19. A thin sheet finite element crack model in eddy current nde10.1109/20.312588 ↗
20. Eddy-current probe impedance due to a volumetric flaw10.1063/1.349615 ↗
21. The volume integral method of eddy current modeling: verification10.1007/BF00565776 ↗
22. Recent improvments to the application of the volume integral method of eddy current modeling10.1007/BF00566587 ↗
23. Vector potential integral formulation for eddy current probe response to cracks10.1109/20.825808 ↗
24. Slots vs. cracks in eddy current nde10.1007/BF00742583 ↗