基于铝屏蔽的铁磁性构件缺陷脉冲涡流检测研究

摘要

针对铁磁性金属的缺陷检测，建立了铝屏蔽(真空磁屏蔽)与非屏蔽下的脉冲涡流检测有限元仿真模型，仿真分析了铁磁性材料下的电涡流与磁力线分布，并通过实验证实了仿真分析的有效性。仿真与实验结果表明：铝屏蔽下的脉冲涡流检测方法能有效的提高铁磁性材料的表面缺陷检测灵敏度，但对铁磁性金属内部缺陷检测效果不明显。%Aiming at the defects detection of ferromagnetic, the circle probes of the finite element models with aluminum shielding (vacuum magnetic shielding)and without shielding were built. Distribution of eddy current and magnetic field for two metal materials were simulated. The validity of simulation analysis was demonstrated by experimental results. The results show that the aluminum magnetic shielding of pulsed eddy current can improve effectively the sensitivity on surface defects of ferromagnetic metal. However, it is not obvious that it can not improve the sensitivity of internal defects of ferromagnetic metal defects.