中文摘要：

运用磁力显微镜观察外磁场作用下缺陷处的微磁场变化,通过分析缺陷附近磁畴的变化特征得出材料中存在缺陷时,缺陷对畴壁形成钉扎,使得缺陷两侧形成反向势垒,阻碍了畴壁运动,在缺陷边缘附近导致磁荷聚集,形成微磁固定结点,由于微磁固定结点内磁化强度的法向分量不连续,缺陷区形成泄漏微磁场,泄漏微磁场的奇异特征包含了缺陷信息,为缺陷微磁生成机理和微磁检测研究提供了理论和实验支撑.

英文摘要：

The change of the magnetism of the defects observed by magnetic force microscope is introduced, the characteristics of the change of magnetic domain near the defects indicate that the defects in the materials pin the magnetic domain walls, reverse potential vallum which prevent the magnetic domain wails from moving was formed in the two side of the defects and magnetic charge collect in the edge of the defects which was called micro-magnetic fixed knots. The discontinuous normal component of the magnetization strength in the micro-magnetic fixed knots results in flux leakage magnetic field whose single characteristics contain the information of the defects. The above conclusions provide a support theoretically and experimentally for the research of the micro-magnetic testing and the mechanism of the defect micro-magnetic.