声发射检测方法对金属构件进行健康检测的关键问题:通过合适的载荷使得构件产生声发射信号。现阶段大部分声发射检测均采用接触式离线加载,本文声发射检测采用可在线检测的非接触式电磁加载。文章首先从电致位错、自由电子运动理论出发,在微观层面探究电磁声发射的机理特征;其次研究静磁场与涡流分布作用下电磁声发射特征差异;基于声发射信号的非平稳特征,利用希尔伯特黄变换方法分析电磁声发射特征。通过改变水平磁场激励方向,实现本征模态函数的能量比值、互相关系数、特征本征模态函数时频图与裂纹指向特征之间的关系联立。
Abstract
The key problem for the metallic structures’ health monitoring using the acoustic emission(AE) method is to establish a relationship between a suitable load and structures’ AE signals excited.But the current AE tests mostly use an offline loading on structures with the contact method.Here,an AE testing method using a contactless local electromagnetic online loading was proposed.Firstly,the mechanism of electromagnetically induced acoustic emission(EMAE) was studied at a microscopic level based on the electro induced dislocation and free electron movement theory.Secondly,the characteristic differences of EMAE signals under various electromagnetic loading conditions were studied,the emission characteristics of the collected nonstationary EMAE signals were studied with Hilbert-Huang transformation.Finally,the relationships among the energy percentage of intrinsic mode functions(IMFs),the cross-correlation coefficients of IMFs,the time-frequency figures of IMFs and crack orientation were established through changing the excitation direction of horizontal magnetic field.
关键词
电磁声发射 /
水平磁场 /
希尔伯特黄变换 /
裂纹指向性
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Key words
electromagnetically induced acoustic emission /
horizontal magnetic field /
Hilbert-Huang transformation /
crack orientation
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参考文献
[1] Gongtian Shen, Zhanwen Wu, Junjiao Zhang. Advances in acoustic emission technology[M]. Springer Proceedings in Physics, New York, America,2015.
[2] Finkel P, Godinez V, Miller R, et al. echnique for damage evaluation. American Inst. of Physics Conf. Proc. [C],2001,557: 1747-1754.
[3] Finkel P, Godinez V. Electromagnetic simulation of ultrasonic signal for nondestructive detection of ferromagnetic inclusions and flaws [J]. IEEE Transactions on Magnetics, 2004, 40 (4) : 2179-2181.
[4] 刘素贞,金亮,张闯,等. 电磁声发射检测技术的涡流激励方法 [J]. 电工技术学报,2012,27(7) :153-159.
LIU Su-zhen, JIN Liang, Chuang Zhang, et al. Eddy Current Exciting Method for Electromagnetically Induced Acoustic Emission Detecting Technique [J]. Trans. of China Electrotechnical Society. 2012, 27(7) :153-159.
[5] 唐力伟,张晓涛,王平. 管状金属构件裂纹电磁声发射激发特性试验研究 [J]. 振动与冲击,2014,33(19) :48-51.
TANG Li-wei, ZHANG Xiao-tao, WANG Ping. Tests for exciting features of electromagnetic acoustic emission of tubular metal parts’crack [J]. Journal of vibration and shock, 2014, 33(19): 48-51.
[6] Lei Guana, Guoyi Tang, Paul K.Chu, Recent advances and challenges in electroplastic manufacturing processing of metals [J] Journal of Materials Research, 2010, 25(7): 1215-1224.
[7] Dalong Li, Enlin Yu, Zhoutong Liu. Microscopic mechanism and numerical calculation of electroplastic effect on metal's flow stress [J]. Materials Science and Engineering A, 2013, 580: 410-413.
[8] Stephen D. Antolovich, H.Conrad, The effects of electric currents and fields on deformation in metals, ceramics, and ionic materials: an interpretive survey [J]. Materials and Manufacturing Processes, 2004, 19(4): 587-610.
[9] H.Conrad. Thermally activated plastic flow of metals and ceramics with an electric field or current [J]. Materials Science and Engineering A, 2002, 322:100-107.
[10] Gronostajski, Z. The constitutive equations for FEM analysis [J]. Journal of Materials Processing Technology, 2000, 106: 40-44.
[11] Jin Bok Chung, Elijah Kannatey Asibu. Acoustic emission from plastic deformation of a pure single crystal. Journal of Applied Physics [J]. 1992, 72(5). 1812-1820.
[12] 刘贵杰,徐萌,王欣,等. 基于HHT的管道阀门内漏声发射检测研究 [J]. 振动与冲击,2012,31(23) :62-66.
Liu Gui-jie, Xu Meng, Wang Xin, et al. AE detection for pipeline valve leaklage based on HHT [J]. Journal of vibration and shock, 2014, 33(19): 48-51.
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脚注
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