锰锌铁氧体空心纤维的制备及其磁性能

PREPARATION AND MAGNETIC PROPERTIES OF Mn-Zn FERRITE HOLLOW FIBERS

以柠檬酸及金属盐为原料,采用有机凝胶-热分解法制备出Mn_(1-x)Zn_xFe_2O_4(X=0.2～0.8)铁氧体空心纤维。通过Fourier红外光谱、热重-差示扫描量热仪、X射线衍射和扫描电镜分别对凝胶前驱体的结构、热分解过程及热处理产物的物相和形貌进行了表征,用振动样品磁强计对纤维的磁性能进行了检测。结果表明:所得Mn_(1-x)Zn_xFe_2O_4铁氧体空心纤维的晶粒尺寸约为lOnm,纤维表面光滑、致密,直径在0.5～5.0μm之间,且具有较大的长径比。纤维的饱和磁化强度和矫顽力以及平均晶粒尺寸都随焙烧温度的升高和保温时间的延长而增大,400℃热处理制得的Mn-Zn铁氧体纤维由于其晶粒粒径小于临界尺寸而表现出超顺磁特征。随Zn含量的提高,纤维的饱和磁化强度先增加后减小,在x=0.63附近达到最大值,而矫顽力在x=0.43左右达到最小值。具有形状各向异性的Mn-Zn铁氧体空心纤维的矫顽力明显高于经相同工艺制得的同组分粉体的矫顽力。

Mn_(1-x)Zn_xFe_2O_4(x=0.2-0.8)ferrite hollow fibers were successfully prepared via the organic gel-thermal decomposition process using metal salts and citric acid as raw materials.The structure,thermal decomposition process and morphologies of the gel precursors and the fibers derived from thermal decomposition of these precursors were characterized by Fourier transform infrared spectroscopy,X-ray diffraction,thermogravimetric and differential scanning calorimetry and scanning electron microscopy,and the ma...