作者：龙小江1,2, 黄丽霞1, 何才厚2, 李秋锋1, 王磊3, 卢超1, 尤立华1
作者单位：1. 无损检测技术教育部重点实验室(南昌航空大学), 江西 南昌 330063;
2. 江西省特种设备检验检测研究院鹰潭分院, 江西 鹰潭 335000;
3. 西南油气田分公司安全环保与技术监督研究院, 四川 成都 610051
关键词：声发射检测;广义S变换;时频分析;损伤特征
摘要：
声发射技术具有实时动态监测的优点，因此其应用越来越广泛，但采用声发射技术对材料和结构的损伤进行定量评估及寿命预测还没有解决办法。提出采用广义S变换对钢材声发射检测信号进行时频分析，通过分析信号时频特征可达到评价钢材损伤各个阶段的目的。首先通过理论分析和仿真信号处理研究，验证广义S变换具有更高时频分辨率；然后在钢材拉伸实验中建立声发射监测系统，采集钢材拉伸损伤各个力学阶段的声发射信号进行时域和频域特征分析；最后采用广义S变换处理，通过时频处理结果可获得钢材在各个损伤阶段的有明显差异的声发射信号时频特征，可为今后钢材使用过程中的损伤定量和寿命预测提供可靠参考依据。
Acoustic emission evaluation method of steel tensile damage based on generalized S transform
LONG Xiaojiang1,2, HUANG Lixia1, HE Caihou2, LI Qiufeng1, WANG Lei3, LU Chao1, YOU Lihua1
1. Key Laboratory of Nondestructive Testing, Ministry of Education, Nanchang Hangkong University, Nanchang 330063, China;
2. Yingtan Branch of Special Equipment Inspection and Research Institute of Jiangxi, Yingtan 335000, China;
3. Safety Environment & Technology Supervision Research Institute, Southwest Oil & Gasfield Company, Chengdu 610051, China
Abstract: Acoustic emission technology has the advantages of real-time dynamic monitoring, so it is used more extensively than others. However, there is still no solution for quantitative evaluation and life prediction of damage to materials and structures based on acoustic emission technology. So generalized S transform was recommended to be adopted to carry out real-time analysis for acoustic emission detection signal, and the purpose of evaluating the steel damage at different stages can be achieved by analyzing the time-frequency characteristics of signal. Firstly, the higher time-frequency resolution of generalized S transform was verified through theoretical analysis and simulation signal processing research, and then the acoustic emission monitoring system is established during the steel tensile test, to collect the acoustic emission signals at each mechanics stage of steel tensile damage for time-domain and frequency-domain characteristics analysis. Finally, based on generalized S transform processing and time-frequency processing results, AE signal time-frequency characteristics of steel with obvious differences at each damage stage can be obtained, which can provide reliable reference for damage quantitative analysis and service life prediction of steel when using in the future.
Keywords: AE testing;generalized S transform;time-frequency analysis;damage characteristics
2018, 44(1): 129-135 收稿日期: 2017-05-28;收到修改稿日期: 2017-07-25
基金项目: 国家自然科学基金资助项目（11264032，11374134，11764030）；江西省自然科学基金资助项目（20122BAB201024）；国家质检总局科技计划项目资助项目（2013zjjz180）；航空科学基金资助项目（2014ZD56007）；2016年度江西省质监局科技计划项目资助（11）
作者简介: 龙小江(1988-),男,江西吉安市人,硕士研究生,专业方向为超声检测技术。
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