【摘要】 基于缺陷周围磁场异常变化的检测原理,通过磁场检测和运动控制的结合,建立了基于霍尔传感器和三维机械运动平台的缺陷区域检查和定位系统.利用该系统对浸泡在液氮中的超导带材BI2121(长5cm宽1cm)进行磁显微测量,可以观察超导带材自场分布.根据毕奥萨伐尔定律,磁场值经过二维傅里叶逆运算确定电流密度分布,观察电流密度异常分布推断出被测样品缺陷的位置和大小.实验结果表明霍尔探头扫描显微镜是一个诊断超导体特性有用的工具,为无损检测技术提供一种快速简便的方法.更多还原

【Abstract】 Based on the detection principle of variations magnetic field around defects,the detection and location system using hall sensor and 3Dmechanical motion platform is established through the combination of magnetic field detection and motion control.The system was used to measure the magnetic field of BI2121(long is 5cm wide is 1cm)immersed in liquid nitrogen.Therefore the self-fields distribution of superconducting tapes can be observed.According to Biot-Savart law,current density distribution is determined by two-dimensional Fourier inverse operation.Therefore,observing the abnormal distribution of the current density can determine the location and size of the defects in the samples.The experimental results show that the hall probe scanning microscope is a useful tool to diagnose superconductor characteristics.It provides a fast and simple method for nondestructive testing.更多还原