缝类缺陷的Lamb波检测

详细信息

Lamb Waves Testing of Slot Defects

摘要: 在ST12冷轧板上用线切割加工出不同深度的狭缝来模拟钢板中的缝类缺陷, 采用一发一收方式, 对缺陷进行Lamb波检测。利用短时傅里叶变换对有无缺陷时采集的时域信号进行了时频分析, 有效识别出板中激发的Lamb波模式; 将时间中心和频率中心作为数字参量, 探讨了缝类缺陷对Lamb波的影响。结果表明, Lamb波信号时间中心的变化与缝类缺陷深度有较好的对应关系。
- Lamb波检测 /
- 短时傅里叶变换 /
- 时频分析 /
- 缝类缺陷
Abstract: Slots with different depth were made by WEDM in metal sheet of ST12 to simulate slot-type defects, and the Lamb waves were stimulated by pitch catch method. The time domain signals obtained in the plates with and without defect, respectively, were analyzed in time-frequency domain by Short Time Fourier Transform. The lamb wave modes were recognized successfully, and the effects of slot-type defects on Lamb waves was discussed by the time center and the frequency center as digital parameter. The result showed a good corresponding relationship between slot depth and the time center of the lamb wave.
- Lamb wave testing /
- Short time Fourier transform /
- Time-frequency analysis /
- Slot defects

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