Depth evaluation for surface-breaking cracks with mode-converted Rayleigh waves generated by a point-focused laser
发布时间：2025-04-30
点击次数：
- 发布时间：
- 2025-04-30
- 论文名称：
- Depth evaluation for surface-breaking cracks with mode-converted Rayleigh waves generated by a point-focused laser
- 发表刊物：
- Optics & Laser Technology
- 摘要：
- In this paper a novel method was developed to quantitatively evaluate the depth of surface-breaking cracks with laser ultrasound testing method. Aluminum alloy blocks with slots of different depth were investigated numerically and experimentally. A three-dimensional numerical model based on discontinuous Galerkin finite element method and quartic Lagrange elements was established to study the interaction of Rayleigh surface waves generated by a point-focused laser with surface cracks. The numerical results showed that the time interval between reflected and mode-converted Rayleigh waves depended on the crack depth and the incident angle of mode-converted shear waves. However, the incident angle tended to be a constant value when the depth of crack was greater than the minimum wavelength of laser Rayleigh waves. An expression for crack depth evaluation was given analytically. The experiment results agreed well with the numerical simulation and demonstrated that this time-of-flight method can be used to accurately evaluate the depth of crack. For cracks with the depth greater than the Rayleigh mode wavelength, a fixed incidence angle can be used to estimate the depth, while for cracks with the depth slightly smaller than the wavelength, the variable incidence angles can be used. This study may provide a feasible idea for laser scanning technology to numerically analyze in large volume objects and quantitatively estimate the depth of surface-breaking cracks.
- 合写作者：
- Runchen Li, Weihua Liu, Zhifeng L, Xiaojian Li, Hang Li Sen Gu, Yaqin Song*
- 卷号：
- 167
- 页面范围：
- 109758
- 是否译文：
- 否
- 发表时间：
- 2023-07-07