基于柔性涡流传感器疲劳裂纹监测试验研究

Research on fatigue crack monitoring experimental based on flexible eddy current sensor

结构健康监测对于保证飞行安全具有重要意义,底层涡流传感器是体系获取结构状态的重要组成。设计了柔性涡流传感器,搭建了预置裂纹监测系统,针对304奥氏体不锈钢、2A12—T4铝合金和TC4钛合金三种材料进行了预置裂纹监测试验。试验表明:对于电导率较小的304奥氏体不锈钢和TC4钛合金材料,最优监测频率增大;预置裂纹对涡流传感器跨阻抗幅值和相位影响不同,相对于幅值变化,相位变化较小;预置裂纹宽度增大会使得传感器跨阻抗变化率增大;柔性涡流传感器感应线圈实现了对裂纹长度的识别和定量监测。

Structure health monitoring has great significance on ensuring safety of flight, eddy current sensor on bottom layer is the key device to obtain state of structurs. The eddy current sensor is designed, prese crack monitoring system is carried out to monitor material of 304 austenitic stainless steel ,2A12-T4 aluminum alloy and TC4 titanium alloy. Experimental result shows that while the optimal frequency increases monitoring of 304 austenitic stainless steel and TCA titanium alloy material,which the conductivity is lower than 2A12-T4 aluminum alloy material, preset crack has different effects on amplitude and phase of transimpedance, amplitude change is greater than phase change ; transimpedance change rate of Sensor increases along with increasing of crack width; the flexible eddy current sensor achieves recognition and quantitative monitoring on crack length.