超声背散射信号包络的缺陷检测。

Flaw detection with ultrasonic backscatter signal envelopes.

机构信息

School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China.

Department of Engineering Science and Mechanics, Penn State University, University Park, Pennsylvania 16802, USA.

出版信息

J Acoust Soc Am. 2019 Feb;145(2):EL142. doi: 10.1121/1.5089826.

DOI:10.1121/1.5089826

PMID:30823796

Abstract

Ultrasound is a prominent nondestructive testing modality for the detection, localization, and sizing of defects in engineering materials. Often, inspectors analyze ultrasonic waveforms to determine if echoes, which stem from the scattering of ultrasound from a defect, exceed a threshold value. In turn, the initial selection of the threshold value is critical. In this letter, a time-dependent threshold or upper bound for the signal envelope is developed based on the statistics governing the scattering of ultrasound from microstructure. The utility of the time-dependent threshold is demonstrated using experiments conducted on sub-wavelength artificial defects. The results are shown to enhance current nondestructive inspection practices.

摘要

超声检测是一种用于检测、定位和评估工程材料缺陷的重要无损检测技术。通常，检测人员会分析超声回波信号，以确定是否超出了阈值。反过来，阈值的初始选择至关重要。在本函中，基于超声微结构散射统计规律，提出了一种基于信号包络的时变阈值或上界。通过对亚波长人工缺陷进行的实验验证了该时变阈值的有效性。研究结果表明，该方法能够提高现有的无损检测技术水平。