Near-field ultrasonic scattering from surface-breaking cracks
Near-field ultrasonic scattering from surface-breaking cracks
复制标题
DOI：
10.1063/1.1476722
复制
发表时间：
2002-04
影响因子：
4
通讯作者：
J. Blackshire;S. Sathish
中科院分区：
文献类型：
--
作者：
J. Blackshire;S. Sathish
本文用扫描外差干涉法研究了表面破裂裂纹对超声瑞利波的近场散射。在散射点的近场观察到明显的二维局部位移模式，这为检测和表征缺陷提供了有效的工具。观察到的图案显示裂纹面附近的超声位移水平急剧增加（2×-4×），从而使裂纹易于与背景水平区分开。一个简单的解释增加近场位移振幅是基于波的传播和自由边界反射参数。
The near-field scattering of ultrasonic Rayleigh waves from surface-breaking cracks has been studied using scanning heterodyne interferometry. Distinct two-dimensional, localized displacement patterns were observed in the near field of the scattering sites, which provide an effective tool for detecting and characterizing the defects. The observed patterns showed a dramatic increase (2×–4×) in the ultrasonic displacement levels near the crack faces, allowing the cracks to be easily distinguished from background levels. A simple explanation for the increased near-field displacement amplitudes is presented that is based on wave propagation and free-boundary reflection arguments.