Correction of ultrasonic array images to improve reflector sizing and location in inhomogeneous materials using a ray-tracing model.
Correction of ultrasonic array images to improve reflector sizing and location in inhomogeneous materials using a ray-tracing model.
复制标题
使用射线追踪模型校正超声波阵列图像，以改善不均匀材料中的反射器尺寸和位置。
DOI：
10.1121/1.3372724
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
S. Rokhlin
中科院分区：
文献类型：
--
作者：
G. Connolly;M. J. S. Lowe;J. A. G. Temple;S. Rokhlin
近年来，由于超声阵列能够执行多种类型的检查并通过对接收的信号进行后处理来产生结构的图像，因此超声阵列的使用显著增加。相控阵在检测具有空间变化的各向异性的非均匀材料方面比传统的换能器有许多优点。本文以奥氏体钢焊缝作为一种典型的非均匀材料为研究对象。给出了通过先前开发的非均匀焊缝模型的射线跟踪方法，特别强调了材料不均匀所带来的困难。计算该结构的延迟律，并使用该延迟律在阵列采集的信号数据的后处理阶段执行合成聚焦。对于模拟的奥氏体焊缝，通过考虑材料的不均匀性和各向异性，与忽略这些的情况相比，可以得到更好的反射面位置(因此，更好的尺寸)。因此，这幅图像被认为已经被更正。典型的图像是由频域中的分析数据和时间域中的有限元模拟数据在各种波模式下产生的，包括模式转换和反射的情况。
The use of ultrasonic arrays has increased dramatically within recent years due to their ability to perform multiple types of inspection and to produce images of the structure through post-processing of received signals. Phased arrays offer many advantages over conventional transducers in the inspection of materials that are inhomogeneous with spatially varying anisotropic properties. In this paper, the arrays are focused on austenitic steel welds as a representative inhomogeneous material. The method of ray-tracing through a previously developed model of an inhomogeneous weld is shown, with particular emphasis on the difficulties presented by material inhomogeneity. The delay laws for the structure are computed and are used to perform synthetic focusing at the post-processing stage of signal data acquired by the array. It is demonstrated for a simulated austenitic weld that by taking material inhomogeneity and anisotropy into account, superior reflector location (and hence, superior sizing) results when compared to cases where these are ignored. The image is thus said to have been corrected. Typical images are produced from both analytical data in the frequency domain and data from finite element simulations in the time domain in a variety of wave modes, including cases with mode conversion and reflections.