【摘要】 基于漏磁检测技术,采用巨磁阻抗GMI传感器搭建了钢板无损检测系统,对镀锡DI材带钢上直径大小为60~140μm的缺陷进行了检测。GMI传感器敏感核心元件采用的是直径16μm、长为5mm的Co68.15Fe4.35Si12.5B15非晶玻璃包裹丝,以非线性非对角模式工作,具有高灵敏度、快速响应、非接触、功耗小、无磁滞等优点。实验表明,这套测试系统在提离值0.5~3 mm范围内能够精确地检测出直径大于60μm的缺陷,根据测量信号可以分析出缺陷所在的位置和大小。实验结果较好地符合磁偶极子模型。更多还原

【Abstract】 In this work, a MFL testing system based on giant magneto impedance(GMI) sensors was set up. The system was used to test DI steels with the crack of 60 μm to 140 μm in diameter. The GMI sensors whose sensing elements are Co68.15Fe4.35Si12.5B15 amorphous microwires with a diameter of 16 mm and a length of 5 mm, working in nonlinear and off-diagonal mode, have the advantages of high sensitivity, fast response, non-contact, low consumption, and no magnetic hysteresis. The experimental results show that the testing system can accurately identify the position and size of the cracks with lift-off value between 0.5mm and 3 mm. The experimental data agrees well with the magnetic dipole model.更多还原