CAJ | 학술논문

电磁超声换能器(electromagnetic acoustic transducer， EMAT)接收信号十分微弱，限制了电磁超声无损检测技术的应用。通过对表面波电磁超声换能器进行发射–接收过程多物理场有限元的建模与分析，发现换能器几何参数对其接收性能具有重要影响。为此，在所建有限元模型基础上，利用正交试验设计方法提取了影响 EMAT 接收性能的关键参数并对 EMAT 几何参数进行了优化设计。优化后电磁超声接收电压峰峰值增长为优化前的1.41倍。设计了一种同向6根导线结构的曲折线圈，又将接收电压提高至优化后的3.83倍，大大提高了 EMAT 的接收性能。最后，实验验证了模型和优化设计方法的有效性。
전자초성환능기(electromagnetic acoustic transducer， EMAT)접수신호십분미약，한제료전자초성무손검측기술적응용。통과대표면파전자초성환능기진행발사–접수과정다물리장유한원적건모여분석，발현환능기궤하삼수대기접수성능구유중요영향。위차，재소건유한원모형기출상，이용정교시험설계방법제취료영향 EMAT 접수성능적관건삼수병대 EMAT 궤하삼수진행료우화설계。우화후전자초성접수전압봉봉치증장위우화전적1.41배。설계료일충동향6근도선결구적곡절선권，우장접수전압제고지우화후적3.83배，대대제고료 EMAT 적접수성능。최후，실험험증료모형화우화설계방법적유효성。
ABSTRACT:The receiving signals of electromagnetic acoustic transducers (EMATs) are extremely weak, which confines their application in nondestructive testing. A multi- physical finite element model was presented to study the ultrasonic generation and reception processes of surface wave EMATs. Simulation analysis revealed that the receiving performance of EMAT was greatly affected by EMAT parameters. As a consequence, based on the established model and by using orthogonal test method, the EMAT’s key parameters that significantly influence the receiving performance were extracted and the geometrical parameters were optimized. After optimization, the peak-to-peak amplitude of induced voltage in EMAT increased to 1.41 times of that in the original EMAT. A meander-line coil with six wires in series was designed, which increased the induced voltage to 3.83 times of the optimized one and the receiving performance of EMAT was greatly improved. The validity of the model and the optimal design method were verified by the experiments.