传感技术学报
傳感技術學報
전감기술학보
Journal of Transduction Technology
2015年
4期
498-502
,共5页
江念%王召巴%陈友兴%陈玉
江唸%王召巴%陳友興%陳玉
강념%왕소파%진우흥%진옥
电磁超声%无损检测%厚度测量%激励频率%提离距离
電磁超聲%無損檢測%厚度測量%激勵頻率%提離距離
전자초성%무손검측%후도측량%격려빈솔%제리거리
electromagnetic ultrasonic%nondestructive testing%thickness measurement%excited frequency%lift-off distance
为提高电磁超声检测信号的信噪比,研究激励信号频率、脉宽及换能器提离距离对厚度测量结果的影响,搭建了电磁超声实验系统。该系统利用RITEC-SNAP 5000产生高能正弦波激励电磁超声换能器EMAT ( Electromagnetic Acoustic Trans-ducer),通过调节激励信号的频率、脉宽,改变提离距离来观测超声回波幅度的变化。实验结果表明:当激励频率和EMAT固有频率相同时其换能效率最高,采用6个周期的脉冲串时前后波包之间分界明显,为获得较大的回波幅度应尽可能减小提离距离。
為提高電磁超聲檢測信號的信譟比,研究激勵信號頻率、脈寬及換能器提離距離對厚度測量結果的影響,搭建瞭電磁超聲實驗繫統。該繫統利用RITEC-SNAP 5000產生高能正絃波激勵電磁超聲換能器EMAT ( Electromagnetic Acoustic Trans-ducer),通過調節激勵信號的頻率、脈寬,改變提離距離來觀測超聲迴波幅度的變化。實驗結果錶明:噹激勵頻率和EMAT固有頻率相同時其換能效率最高,採用6箇週期的脈遲串時前後波包之間分界明顯,為穫得較大的迴波幅度應儘可能減小提離距離。
위제고전자초성검측신호적신조비,연구격려신호빈솔、맥관급환능기제리거리대후도측량결과적영향,탑건료전자초성실험계통。해계통이용RITEC-SNAP 5000산생고능정현파격려전자초성환능기EMAT ( Electromagnetic Acoustic Trans-ducer),통과조절격려신호적빈솔、맥관,개변제리거리래관측초성회파폭도적변화。실험결과표명:당격려빈솔화EMAT고유빈솔상동시기환능효솔최고,채용6개주기적맥충천시전후파포지간분계명현,위획득교대적회파폭도응진가능감소제리거리。
In order to improve the SNR of the thickness measurement testing,study the effects caused by the excita-tion signal and transducer lift-off distance, setting the electromagnetic ultrasonic experiment system. Using the system RITEC-SNAP 5000 produced high-energy sine wave to excite the electromagnetic ultrasonic transducer ( EMAT) ,by adjusting the frequency of the excitation signal,pulse width,change the lift-off distance to observe the change of the ultrasonic echo amplitude. The experiment results showed that,when the excitation frequency was e-qual to the inherent frequency of EMAT,the transducer high worked efficiency;using six cycles of pulse sequence, the wave boundary between before and after was apparent;in order to obtain larger echo amplitude,the lift-off dis-tance should be minimized.