> Ⅰ. INTRODUCTIONCo-coated γ-Fe 2 O 3 magnetic powder is a new magnetic recording material developed in recent years. It is divided into two sorts: Co-doped γ-Fe 2 O 3 （known as Co-γ-Fe 2 O 3 ） and Co-ferrite epitaxial γ-Fe 2 O 3 （known as CoFe-γ-Fe 2 O 3 ）. The coercivity of Co-coated γ-Fe 2 O 3

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">用直流磁控溅射技术在玻璃衬底上制得了金属Fe/Cu超晶格薄膜。用X射线衍射和电子显微镜观察和分析了它们的调制特性和晶格结构;用铁磁共振（FMR）技术和振动样品磁强计进行了磁学性质的研究。新的实验结果揭示了在邻近Fe层间的耦合特性和它对超晶格磁性的影响。</span>

I. INTRODUCTIONThe outstanding magnetic properties of Nd-Fe-B permanent alloy with very high coercive force and maximum magnetic energy product have attracted scientists’ attention greatly and extensive investigation has been made on its structure and mag-

The four stages of the demagnetization process of oriented sintered Nd-Fe-B alloy after saturation magnetizing along easy direction is studied theoretically in this paper. The results indicate that the nucleation in the soft magnetization regions located at the surface of hard magnetic grains, as well as the irreversible domain wall displacement from the surface to the inside of grains are the dominant factors controlling the intrinsic coercivity of Nd-Fe-B alloy. The rapid reduction of coercivity of Nd-Fe-B alloy with temperature rising are mainly attributed to the thermal movement of atoms it has a harmful effect on the perfection of tetragonal structure in hard magnetic grains and increases the thickness of the soft magnetization transition regions.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">用射频溅射法系统研究了非晶态CoFeNiNbSiB软磁薄膜的制备工艺,发现在0.5Pa的低氩气压下,可以得到性能优良的软磁薄膜,而且膜的性能受衬底偏压影响很小.经旋转磁场退火热处理后,膜的起始磁导率一直到10MHz都可在3000以上,表现出良好的频率特性.用电阻法研究了非晶膜在退火过程中的结构变化过程,发现高温下非晶膜明显经历了四个连续的阶段。</span>