脉冲漏磁检测技术中传感器性能影响因素研究

Study on effect factors of sensor performance in pulsed magnetic flux leakage testing

漏磁检测技术广泛应用于铁磁性材料的检测。脉冲漏磁检测采用脉冲激励对被测试件进行局部磁化,它的优点是能对较大提离下的铁磁性材料实现缺陷检测。分析了2种不同截面激励线圈下传感器的灵敏度情况,确定矩形截面激励线圈灵敏度高、受提离影响明显;并采用有限元法对矩形激励线圈厚度、匝数密度、尺寸大小及磁轭极靴高度、两极靴间距等对检测结果与提离值之间的关系进行分析,为合理选择传感器参数及优化传感器性能提供依据。

Magnetic flux leakage（MFL） testing technique is commonly used in the inspection of ferromagnetic materials.Pulsed magnetic flux leakage testing（PMFL） technique locally magnetizes the specimen under test with pulse excitation.The advantage of this technique is that it can realize defect detection of ferromagnetic materials with large lift-off value.Sensors with rectangular and cylinder exciting coils are studied.The sensor with rectangular exciting coil has higher sensitivity and is more sensitive to lift-off value.The effects of the thickness,turn density and area of the coil,the height of yoke pole and the distance between two yoke poles on detection results and lift-off value are investigated using finite element method（FEM）,which provides a reference for determining exciting coil parameters and optimizing sensor performance.