基于偏置磁场EMAT表面波换能器效率的分析  

Analysis of efficiency of EMAT surface wave transducer based on bias magnetic field

作　　者：张义涛 程树云 陆铭慧[2] 朱颖[2] 胡克 戴昱辉 ZHANG Yitao;CHENG Shuyun;LU Minghui;ZHU Ying;HU Ke;DAI Yuhui(College of Mechanical&.Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 21o016,China;Key Laboratory of Nondestructive Testing Technology,Ministry of Education,Nanchang University of Aeronautics,Nanchang 330063,China;Lingyun Technology Group Co.,Ltd.,Wuhan 430040,China)

机构地区：[1]南京航空航天大学机电学院,南京210016 [2]南昌航空大学无损检测技术教育部重点实验室,南昌330063 [3]凌云科技集团有限责任公司,武汉430040

出　　处：《无损检测》2023年第11期59-66,共8页Nondestructive Testing

摘　　要：为提高常规EMAT(电磁超声)换能器效率,设计一种新型偏置磁场EMAT换能器。利用有限元软件建立EMAT激励表面波的二维仿真模型,对比分析常规和偏置EMAT对激励表面波的影响。最后设计正交试验研究磁铁高度、磁铁宽度、线圈高度、线圈宽度和线圈提离对偏置EMAT激励表面波的影响规律,并通过试验验证了其准确性,此外还研究了偏置磁铁对接收EMAT的影响。结果表明,偏置EMAT换能器激励的表面波幅值比常规EMAT的提高了51%,并且该方法不会在频域信息上发生主频分叉畸变问题,采用偏置EMAT接收的信号幅值比常规EMAT的提高了38%,偏置EMAT能有效提高检测灵敏度。In order to improve the conversion efficiency of the conventional Electromagnetic Acoustic Transducer(EMAT)surface wave transducer,this paper proposes a new type of biased magnetic field EMAT transducer.A two-dimensional simulation model of EMAT excited surface wave is established using finite element software to compare and analyze the influence of conventional and biased EMAT on the excited surface wave.Finally,an orthogonal experiment is designed to study the influence of magnet height,magnet width,line height,line width,and coil lift on the excited surface wave of the biased EMAT.The accuracy of the orthogonal experiment was verified by experiment.In addition,the influence of biased magnet on the receiving EMAT was also studied.The research results showed that the amplitude of the excited surface wave of the biased EMAT was 51%higher than that of the conventional EMAT,and this method does not cause main frequency bifurcation distortion in the frequency domain information.The amplitude of the receiving signal using the biased EMAT was 38%higher than that of the conventional EMAT,and the biased EMAT can effectively improve the detection sensitivity.

关 键 词：表面波电磁超声换能器 正交试验 换能效率 优化设计 

分 类 号：TG115.28[金属学及工艺—物理冶金]