|
|||||
 |
|
|
|
|
|
So\dots is this a
surface-breaking crack?
Milan Poznic and Claudio Pecorari |
|
Vol. 1 (2006), No. 4, 743–762
|
Abstract |
|
An inspection technique used to assess the structural integrity of critical components in a nuclear power plant must be able to discern surface-breaking cracks from subsurface cracks. This work proposes an ultrasonic method to provide that information and presents a theoretical investigation into it. The main assumption of the model is that water carried by pressurized pipes infiltrates and fills a surface-breaking crack, while a subsurface crack is dry. The model simulates an inspection in which the modulation technique is employed and the surface hosting the crack is not accessible. A ratio, , constructed with signals recorded in backscattering configuration during a modulation cycle, is examined and shown to provide a clear criterion allowing subsurface cracks to be distinguished from surface-breaking cracks when a shear vertical wave at 45 degree incidence is employed as a probe. |
Keywords
partially closed cracks, modulation, wave scattering
stress-corrosion
|
Milestones
Received: 15 December 2005
Revised: 7 February 2006
Accepted: 30 March 2006
Published: 1 August 2006
|
Authors |
| Milan Poznic | |
| Marcus Wallenberg Laboratory Department of Aeronautical and Vehicle Engineering Royal Institute of Technology SE 10044 Stockholm Sweden |
|
| Claudio Pecorari | |
| Marcus Wallenberg Laboratory Department of Aeronautical and Vehicle Engineering Royal Institute of Technology SE 10044 Stockholm Sweden |
|
|
