基于旋转交流电磁场的铁磁材料裂纹方向检测

Crack Direction Detection of Ferromagnetic Materials Based on Rotating Alternating Current Electromagnetic Field

针对传统交流电磁场检测(Alternating Current Filed Measurement,ACFM)技术检测任意方向裂纹容易出现误检、漏检等问题,引入旋转磁场作为ACFM技术检测探头的激励源,设计了一种新型阵列式无损检测探头。建立以旋转磁场为激励源的ACFM技术检测探头有限元仿真模型,融合多个采样点提取工件表面的磁场信号,分析了不同方向的铁磁材料表面裂纹的磁场分布情况。仿真结果表明,以采样点所检测到磁场信号的By-Bx特性曲线长轴倾斜角度为裂纹缺陷特征值,可以有效地检测出不同方向的裂纹缺陷,为铁磁性材料表面裂纹方向检测提供一种新的方法。

Aiming at the problems that easy to occur in the detection of cracks in arbitrary directions by tradi-tional alternating current filed measurement(ACFM)technologies,a new array nondestructive detection probe is designed.A rotating magnetic field is introduced as the excitation source of ACFM detection probe.A finite element simulation model of an ACFM probe with a rotating magnetic field as the excitation source is estab-lished.The magnetic field signals on the workpiece surface are extracted by integrating multiple sampling points,and the magnetic field distribution of surface cracks in ferromagnetic materials in different directions is analyzed.The simulation results show that the crack defects in different directions can be effectively detected by taking the tilt angle of the long axis of the By-Bx characteristic curves of the magnetic field signal detected at the sampling point as the characteristic value,which provides a new method for the surface crack direction detection of ferromagnetic materials.