摘要
针对钛合金损伤在役监测需要,提出采用声发射实时动态监测技术。为了对钛合金中裂纹声发射源做特征分析,利用有限元分析方法,通过建立钛合金二维模型,采用3种力源函数对材料中不同类型、不同中心频率与不同传导距离的裂纹声发射源开展研究,并结合频散曲线,利用小波方法分析声发射源的特征频率与模态。结果表明:双极子源在平行X轴源方向产生的结果整体上非常清晰,在中低频范围与S0模态一致;但在Z轴源方向,对于特征频率为0~200 kHz时未能明显体现Lamb波产生波形的模态。单极子源1平行X轴源方向产生的结果在中高频高幅值区域最清晰,但在低频处的混叠,不易对模态进行识别;在Z轴源方向,A0模态识别最清晰。单极子源2平行X轴源方向产生的结果最精准地反映了中心频率,但对于S0模态识别的清晰度要弱于其他2种源的结果;Z轴源方向也同样反映出清晰度较弱。采用断铅实验的验证结果与仿真结果较一致,说明仿真结果的可靠性。
In order to meet the needs of in-service monitoring of titanium alloy damage, an acoustic emission real-time dynamic monitoring technology was proposed. For analyzing the characteristics of crack acoustic emission sources in titanium alloy, a twodimensional model of titanium alloy was established with finite element analysis method. Three kinds of force source functions were used to study the crack acoustic emission sources with different types, different center frequencies and different conduction distances in the material. And the characteristic frequencies and modes of the acoustic emission sources were analyzed through wavelet method by combining dispersion curves. It is found that the bipolar source produces clear results in the direction parallel to the Xaxis source, which are consistent with S0 mode in the middle and low frequency range. However, in the Z-axis source direction, the characteristic frequency is always within 0~200 kHz, which fails to clearly demonstrate the waveform mode generated by Lamb wave. The monopole source 1 parallel to the X-axis source direction produces the clearest results in the middle high frequency and high amplitude region, but it is difficult to identify the mode at the low frequency due to the aliasing. In the Z-axis source direction,A0 mode identification is the clearest. The result of monopole source 2 parallel to the X-axis source direction is the most accurate to reflect the center frequency, but the clarity of S0 mode identification is weaker than those of the other two sources. The Z-axis source direction also reflects the weak definition. Finally, the simulation results are consistent with the verification conclusion employing the lead-breaking experiment, validating its reliability.
作者
李秋锋
康晨
魏鑫成
周瑞琪
董德秀
黄丽霞
LI Qiu-feng;KANG Chen;WEI Xin-cheng;ZHOU Rui-Qi;DONG De-xiu;HUANG Li-xia(Key laboratory of Nondestructive Testing Technology(Ministry of Education),Nanchang Hangkong University,Nanchang 330063,China;AECC Shenyang Liming Aero-Engine Co.,Ltd.,Shenyang 110043,China)
出处
《失效分析与预防》
2022年第5期316-327,共12页
Failure Analysis and Prevention
基金
国家自然科学基金(11764030)
江西省主要学科和技术带头人资助计划(20204BCJL22039)
江西省自然科学基金重点项目(20212ACB204014)
南昌航空大学研究生创新专项资金项目(YC2021-071)。
关键词
钛合金
声发射
中心频率
特征频率
titanium alloy
acoustic emission
center frequency
characteristic frequency
作者简介
李秋锋(1976年−),男,博士,教授,主要从事声学检测技术与仪器、检测信号处理及高分辨成像等方面的研究。
