SO ... IS THIS A SURFACE-BREAKING CRACK?

作者:Poznic Milan*; Pecorari Claudio
来源:Journal of Mechanics of Materials and Structures, 2006, 1(4): 743-762.
DOI:10.2140/jomms.2006.1.743

摘要

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, R, 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.

  • 出版日期2006-4