铝合金结构疲劳裂纹监测研究

Research on Fatigue Crack Monitoring of Aluminum Structure

针对航空器金属结构裂纹扩展监测的特点和需要,文中提出了一种基于柔性平面的非对称涡流阵列传感器,构建了其半解析正向模型,优化了传感器工作频率、提离距离等参数。然后搭建了基于涡流阵列传感器的结构裂纹在线监测系统,开展了2A-12铝合金裂纹扩展监测实验。模型仿真结果表明:非对称涡流阵列传感器存在最优工作频率,随着提离距离的增加最优工作频率值减小。实验结果表明非对称涡流阵列传感器实现了对2A-12铝合金半孔板试样的实时裂纹监测,监测精度达到了1 mm。

To monitor the crack damage located at metal frame,a kind of unsymmetrical current sensor with flexible and planar features was introduced. Semi-analytical model of the sensor was constructed and the driving frequency and liftoffs were optimized though the constructed model. Fatigue crack monitoring experiment of 2A-12 aluminum alloy specimen was carried out to verify the fatigue crack monitoring capability of sensor. Analysis results show that optimized driving frequency exists under difference liftoffs and the optimized damage monitoring sensitivity decreases with the increasing of liftoffs. Monitoring experiment result indicates that unsymmetrical sensor has a certain ability to monitor the fatigue damage with an accuracy of 1 mm.