基于脉冲漏磁的表面缺陷判别  

Discrimination of surface defects based on pulsed magnetic flux leakage

作　　者：方舟 许鹏 徐中行 FANG Zhou;XU Peng;XU Zhongxing(College of Automation Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]南京航空航天大学自动化学院,南京211106

出　　处：《无损检测》2021年第4期10-15,56,共7页Nondestructive Testing

基　　金：国家重点研发计划资助项目(2018YFB2100903);自然基金委国家重大科研仪器研制项目(61527803);中国铁路总公司科技研究开发计划(2017G003-D);中央高校基本科研业务费(NJ2020014)。

摘　　要：考虑到涡流效应对脉冲漏磁信号的影响,仿真了不同激励电压、不同磁芯相对磁导率、不同缺陷深度和埋藏深度下的缺陷脉冲漏磁信号,发现了检测信号的过冲和波动现象。基于此现象提出了两种近表面或深埋藏缺陷的判别方法,即基于过冲及波动现象的方法以及基于导数极值的方法。最后通过试验验证了上述方法的可行性。In this paper,the effect of eddy current on pulse magnetic flux leakage(PMFL) signals is considered.The PMFL signals of defects under different excitation voltages,relative permeability of the magnetic core,defect depth and burial depth are simulated,and the overshoot and fluctuation phenomena of the defect signals are found.Based on the phenomena,two methods for discrimination of near surface and deep buried efects are proposed,the overshoot and fluctuation phenomena method and the extreme value of the derivative signals method.Finally,the feasibility of the above methods is verified by experiments.

关 键 词：漏磁检测 脉冲漏磁 涡流效应 缺陷分类 

分 类 号：TG115.28[金属学及工艺—物理冶金]