铁磁性金属近表面缺陷的脉冲电磁铁式电磁超声传感器设计及检测方法OA

To overcome the problems of strong magnetic force interference,low transduction efficiency,and poor detection performance existing in current electromagnetic acoustic surface wave transducers when detecting structural defects in ferromagnetic metals,a novel electromagnetic acoustic surface wave transducer based on a U-type pulsed electromagnet with high conversion efficiency and strong adaptability,as well as a corresponding detection method,were designed and developed.Finite element numerical simulation was used to optimize the transducer configuration and verify the feasibility of the detection method.A pulsed electromagnet-type electromagnetic acoustic testing system was established.The effects of pulse number,excitation voltage,and defect size on the transducer performance were analyzed,and the performance differences between this transducer and existing electromagnetic acoustic transducers were compared.The results show that the pulsed electromagnet-type transducer has significantly better near-surface defect detection capability in DH36 low-alloy carbon steel compared to existing electromagnetic acoustic transducers.This study provides a new method for addressing near-surface defects in ferromagnetic metals.