利用Bitter粉纹法观察了未经磁化、受力程度不同的无取向硅钢片试件的磁畴结构，对比分析了应力对磁畴及磁场值ΔB的影响。结果表明：无取向硅钢试件在未受力或应力集中较小时，晶粒内磁畴以180°剑状畴为主，同一晶粒内畴壁相互平行；随着应力集中程度增加，畴壁长度和间距发生改变，出现了迷宫畴，并且随着应力集中程度越大，迷宫畴的数量越多，表面磁场值ΔB越大。试验为探讨磁记忆检测的微观机理提供了依据。

The magnetic domains of silicon steel sheet, which was not magnetized and was loaded on different intensity or direction, were observed with the Bitter method. The effect of stresses on magnetic domains and the magnetic signals ΔB was then analyzed. The results show that there mainly exist 180° gladiate domains for the silicon steel sheet with low load or no load, with their walls being small in the same crystalline grain. Then, with the load enhancing, the domain walls length and space are changed and the mazy domains appear. The number of the mazy domains and the magnetic signals of ΔB increase with the load increasing.