InSb磁敏电阻脉冲涡流传感器的研究

脉冲涡流检测方法是涡流检测技术的一个新兴分支。因脉冲信号频带很宽,比单一频率正弦涡流衰减慢,其瞬态感应电压信号中就包含了有关缺陷的重要信息。本文分析了InSb磁敏电阻作为脉冲涡流检测元件的工作原理,设计了探头结构和调理电路,有效抑制了环境温度的干扰,并分析了应用InSb磁敏电阻的涡流探头检测金属裂纹特征的信息提取方法。实验结果表明,采用InSb磁敏电阻作为脉冲涡流检测传感器,具有较高的裂纹灵敏度,且可以较好地反映裂纹的深度。

Study on pulsed eddy current sensor of InSb magnetoresistor

Pulsed eddy current testing is a new development area of eddy current testing technology. Pulsed signal has wide frequency bandwidth and attenuates slower than single frequency sine eddy current does. And there is important information about cracks in its transient induced voltage. This paper analyzes the working principle of InSb magnetoresistor that is used as eddy current testing sensor. The probe and conditioning circuit of the sensor were designed. Environmental temperature interference was restrained efficiently. This paper introduces the method of extracting characteristics of metal crack signals using eddy current probe with InSb magnetoresistor. Experiment results show that better crack sensitivity is obtained and the crack depth is also tested satisfactorily using InSb magnetoresistor as pulsed eddy current testing sensor.