提高电磁超声探伤灵敏度方法的探讨  

Discussion about method of increasing the electromagnetic acoustic flaw detection sensitivity

作　　者：齐英豪 

机构地区：[1]钢铁研究总院分析测试所,北京100081

出　　处：《物理测试》2015年第5期13-17,共5页Physics Examination and Testing

摘　　要：针对电磁超声检测存在回波信号弱、信噪比低的问题,通过对发射电路采取多级升压以及发射线圈回路进行阻抗匹配的方法,实现电磁超声的大功率发射,以改善检测灵敏度和信噪比。利用设计的发射系统对铝块进行试验,结果表明:随着发射电压提高,回波信号呈线性升高,且信噪比不断增加;合理选用电容值对发射线圈回路进行匹配,同样提高了回波信号的强度。两者相互配合,有助于提高电磁超声探伤灵敏度。To the problem of the weak echo signal and low signal noise ratio of the electromagnetic acoustic testing,by the way of taking the multistage booster in the transmission circuit and impedance matching in the coil circuit,it realized high power emission to improved the detection sensitivity and signal noise ratio. An experiment research for aluminum piece was made through the designed transmission system,it concluded:as the emission voltage increased,the echo signal was improved linearly,the signal-to-noise was also increased. Transmission coil circuit was matched by a reasonable choice of capacitance,it also improved intensity of echo signal. When used together,it would help to improve the electromagnetic acoustic flaw detection sensitivity.

关 键 词：电磁超声换能器(EMAT) 灵敏度 发射功率 阻抗匹配 

分 类 号：TH878.2[机械工程—仪器科学与技术]