脉冲涡流检测信号的同步采样方法

为了有效利用脉冲涡流信号的低频成分检测钢板内部裂纹缺陷,提出了脉冲涡流同步采样方法。介绍了该方法的工作原理;采用在钢板上加工不同规格矩形槽的方法模拟钢板的裂纹缺陷;设计了由激励线圈和检测线圈构成的传感器,实现脉冲涡流信号的提取;采用数据采集卡采集信号,以Labview为平台,实现同步采样方法的软件设计。对钢板缺陷的检测和试验数据的分析,证明了脉冲涡流同步采样方法在钢板内部裂纹缺陷检测中具有较高的灵敏度,可以有效识别钢板内部裂纹缺陷。

The Synchronous Sampling on Pulsed Eddy Current Signals

In order to use the low-frequency components of the pulsed eddy current signal to detect the crack defects in the steel plate effectively,a method of pulsed eddy current synchronous sampling was proposed.The working principle of pulsed eddy current synchronous sampling method was described.Different sizes of rectangular slot in the steel plate were processed to simulate the crack defects in steel plate.A transducer consisting of exciting coil and measurement coil was designed to pick up the pulsed eddy current signal.Signal acquisition was realized by the use of Data Acquisition Card.Based on LabVIEW,the synchronous sampling software was designed.Through the steel plate defect detection and the analysis of experimental data,it was indicated that the method of pulsed eddy current synchronous sampling had a high sensitivity in steel plate internal cracks defect detection and could effectively identify defects in steel plate.