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缝类缺陷。采用一发一收和单发单收两种方式对缺陷进行兰姆波检测,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兰姆波模式以及模式转换现象。进一步分析发现,试件中激发的主要兰姆波模式的能量分布中心与缺陷深度有较好的对应关系。
Slots with different depth were made by WEDM in metal sheet of ST12 to simulate slot-type defects.The Lamb wave was stimulated by pitch-catch and pulse-echo method.The time domain signals obtained in the defect-free plate and the defected ones,respectively,were analyzed in time-frequency domain by Short Time Fourier Transform.The lamb wave modes and mode conversion were recognized successfully.There was a good corresponding relationship between slot depth and the energy distribution center of the main Lamb wave mode.
出处
《无损检测》
北大核心
2007年第11期630-633,649,共5页
Nondestructive Testing
基金
湖北省自然科学基金资助项目(2004ABA019)
湖北省教育厅资助项目(2004D009)
宁波市自然科学基金资助项目(2006A610025)
关键词
兰姆波检测
短时傅里叶变换
时频分析
Lamb wave testing
Short time Fourier transform
Time-frequency analysis
