柔性涡流阵列传感器孔边裂纹监测技术

针对这一问题，提出了一种带双面补强的柔性涡流阵列传感器并用于孔边裂纹监测。通过COMSOL有限元软件建立传感器和被测试验件的有限元模型，分析提离距离、垫片磁导率变化和裂纹扩展对传感器输出信号的影响；制备带补强和不带补强的传感器，并开展挤压实验和在线疲劳裂纹监测实验；根据实验结果和仿真结果之间的差异进行误差分析。结果显示：随着提离距离和垫片磁导率的增加，传感器输出感应电压逐渐增大；传感器裂纹监测灵敏度随着提离距离的增加而逐渐减小；带补强的传感器可以在螺栓拧紧扭矩为63 N·m的条件下工作，而不带补强的传感器在拧紧力矩为50 N·m时完全失效；通过在线疲劳裂纹监测实验验证了带补强的传感器对裂纹具有定量监测能力，裂纹监测精度与激励线圈之间的间距一致，可达1 mm；实验结果与仿真结果之间的差异主要由提离距离引入。

Hole edge crack monitoring technology of flexible eddy current array sensor

A flexible eddy current array sensor with double-side reinforcement is proposed for hole edge crack monitoring. First, with COMSOL finite element method, a finite element model of the sensor and the test piece was established, through which the effects of lift-off, permeability of the gasket and crack growth on the output signals of the sensor were analyzed. Then, sensors with and without reinforcement were prepared and the extrusion experiment and on-line fatigue crack monitoring experiment were carried out, followed by error analysis based on the difference between the experimental results and the simulation results. The results showed that with the increase of lift-off and permeability of the gasket, the output inductive voltage of the sensor increased gradually, while the sensitivity of the crack detection sensor decreased with the mounting lift-off. The sensor with reinforcement can work when the tightening torque was 63 N·m, while the sensor without reinforcement completely failed when the tightening torque was 50 N·m. The online crack monitoring experiments also verified that the sensor with reinforcement has quantitative crack monitoring ability, and the crack monitoring accuracy is consistent with the distance between the excitation coils, which is up to 1 mm. The difference between the experimental results and the simulation results was mainly introduced by the lift-off.