Discrimination method of through-wall cracks in steam generator tubes using eddy current signals

• Published in: NDT & E international : independent nondestructive testing and evaluation Vol. 39; no. 5; pp. 361 - 366
• Main Authors: Hur, Do Haeng, Lee, Deok Hyun, Choi, Myung Sik, Lee, Un Chul, Kim, Seon Jin, Han, Jung Ho
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.2006; Elsevier Science
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Eddy current test; Exact sciences and technology; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); In situ pressure test; Industrial metrology. Testing; Materials science; Materials testing; Mechanical engineering. Machine design; Physics; Solid mechanics; Steam generator tube; Structural and continuum mechanics; Through-wall crack; Eddy current test; Through-wall crack; In situ pressure test; Steam generator tube; Notched test piece; Tube; In situ; Pressurizing; Fatigue crack; Steam generator; Magnetic measurement; Electrical measurement; Discrimination; Plasticity; Crack length; Metrology; Non destructive test; Eddy current testing; Internal pressure
• ISSN: 0963-8695; 1879-1174
• DOI: 10.1016/j.ndteint.2005.10.005

A unique non-destructive technique to discriminate a through-wall crack and to measure the through-wall length of a through-wall crack was developed using the EDM notch specimens and verified by using real fatigue cracks. It is based on the distribution profile of the eddy current signal amplitude along the crack length direction. It was also verified that the internal pressurization of the in situ pressure test induced a plastic deformation of the crack, resulting in a remarkable increase of the signal amplitude.