汇报题目：参加QNDE 2018国际会议总结报告会
汇报时间：2018年7月23日(星期一) 9:00
汇报地点：科技园西五楼南205会议室
汇报人：曹徐伟
会议名称：45thAnnual Review of Progress in Quantitative Nondestructive Evaluation
会议时间：July15-19,2018
会议地点：Burlington, Vermont, USA
会议简介：QNDE is a highly interdisciplinary technology that involves the use of various techniques to detect both manufacturing and service related flaws in materials and structures which are important to safety in essentially all industries. The Annual Review is a week-long technical meeting in which both advances in fundamental knowledge and new engineering applications in several measurement technologies - ultrasonics, eddy currents,X-rays, thermosonics and thermography, among others - are reported and discussed. For more than four decades, the QNDE Conference has been identified as the world's leading research/engineering conference in this specialized engineering field.
会议交流工作
Oral presentation: Corrosion tomography based on cutoff property of A1 mode
报告人：曹徐伟
参加论文信息
Title: Corrosion tomography based on cutoff property of A1 mode
Author: Xuwei Cao, Liang Zeng, Jing Lin
Abstract: Lamb wave shows a great potential for corrosion detection, due to its long range propagation and sensitivity to defects. The lowest order modes are most commonly used for Lamb wave tomography, since pure modes can be easily measured in the excited frequency range. However, the cutoff property of higher order modes is also of importance to determine and describe the corrosion patches. Envelope difference coefficient (EDC) is proposed as a qualitative indicator in this paper to evaluate the effects of corrosion on direct wave packets. Firstly, a toneburst response is extracted from the wideband laser received signal. The center frequency is selected near the cutoff frequency of A1 mode, leading to a preferable resolution for corrosion detection. Subsequently, the extracted signal is compensated for A1 mode to restore the original waveform. The waveform inside a designed window is compared with the reference one, to compute the difference coefficient between their Hilbert envelope curves. Experiments are performed on a corroded aluminum plate. Two cases of the interaction between Lamb waves and corrosion are discussed in detail. Based on our proposed indicator, the probability reconstruction algorithm provides an accurate and robust diagnosis map.
