基于新型脉冲涡流传感器的裂纹缺陷定量检测技术

传统脉冲涡流检测技术采用反射型传感器,其通过一个圆柱形的激励线圈来产生激励磁场,采用检测线圈或霍尔传感器来检测扰动磁场,然而由于激励磁场要比缺陷引起的扰动磁场强很多,使得这种结构的传感器对缺陷的检测灵敏度不高,需采用差分的方法来增强缺陷信息.提出了一种新型脉冲涡流传感器,其通过采用矩形激励线圈来改变激励场的空间分布,使得无需差分就可以对缺陷进行定量.在分析该新型脉冲涡流传感器检测原理的基础上,采用仿真和实验相结合的方法研究了其对裂纹缺陷长度和深度进行定量的效果,仿真与实验结果相一致,证明了该传感器的有效性.

Quantification of Crack Defect Using a New Pulsed Eddy Current Sensor

In traditional pulsed eddy current(PEC) nondestructive testing(NDT) technique usually a reflection-type probe is used,which consists of a pancake exciting coil for generation of incident magnetic field and a pick-up coil or a solid-state magnetic field sensor for detecting the perturbed magnetic field.However,due to the restriction of the traditional structure of PEC probes,the incident magnetic field generated by the excitation coil is much stronger than the eddy current induced magnetic field,thus reducin...