金属磁记忆微观机理试验研究

Experimental research on the microcosmic mechanism of magnetic memory testing

金属磁记忆检测机理中指出:地磁场环境中受载荷作用的铁磁试件,其内部会发生具有磁致伸缩性质的磁畴组织定向和不可逆的重新取向。将未经磁化且弯曲不同角度的无取向硅钢片和未经磁化且施加不同载荷的20#钢压缩试件制作成金相观察试样,利用B itter粉纹法观察受力程度不同的硅钢片和20#钢试件的磁畴结构,对比同种材料不同载荷试样的磁畴结构照片,分析应力对磁畴的影响。试验表明:未受力或应力集中较小时,晶粒内磁畴以片状畴为主,同一晶粒内畴壁相互平行,随着应力集中程度的增加,磁畴结构出现迷宫畴。且应力集中程度越大,迷宫畴个数越多,同时畴壁长度和间距发生改变。

The microcosmic mechanism of magnetic memory testing showed that in the earth magnetic field, the magnetic domain structure of the loaded - ferromagnetic specimens has directional and irreversible reorientation. The indirectional silicon steel sheets without magnetization and with different bending angles and the different loading 20# steels were made into metallographic specimens. The magnetic domain structure of the specimens has been observed with the Bitter method. The results have shown that under no stress or with small concentrated stress, most of the domains are lameUar before loading, with the load enhancing, the labyrinth domains are appearing and the number of the labyrinth domains increases. The domain walls＇length and space changed simultaneously.