M型铁氧体结晶度分析及其对磁性能的影响

Crystallinity Analysis of M-Type Ferrite and Its Effect on Magnetic Properties

本文以M型钡铁氧体BaFe_(12)O_(19)为研究对象,以Jade软件为拟合工具,以BaFe_(12)O_(19)的结晶度计算和探究其合成因素/方法、结晶度及磁性间的内在联系为主要研究目的。采用化学共沉淀法及二次化学共沉淀法制备BaFe_(12)O_(19),对BaFe_(12)O_(19)的XRD谱实现了全谱分峰拟合,通过拟合峰面积计算了化学共沉淀法不同摩尔比n(Fe)/n(Ba)和二次化学共沉淀法不同焙烧温度制备的BaFe_(12)O_(19)的结晶度。结果表明:一定范围内降低n(Fe)/n(Ba)、升高焙烧温度或改变合成方法,可调控BaFe_(12)O_(19)的结晶度,进而引起其磁性参数M_(s)和H_(c)的提高。且结晶度不是M_(s)和H_(c)的单一影响因素,其与片状颗粒径向尺寸均对M_(s)和H_(c)影响明显。

M-type barium ferrite BaFe_(12)O_(19)was prepared by chemical coprecipitation and secondary chemical coprecipitation methods,and the dependence of crystallinity on synthesis factors and magnet‐ic properties was investigated by Jade software.The XRD curves of BaFe_(12)O_(19)were matched by profile peak fit method,and the crystallinities of BaFe_(12)O_(19)prepared by chemical coprecipitation method with different molar ratio of n(Fe)/n(Ba)and secondary chemical coprecipitation method at different calcination temperatures were calculated.The results showed that the crystallinity of BaFe_(12)O_(19)could be regulated by decreasing molar ratio of n(Fe)/n(Ba),increasing the calcination temperature or changing the synthesis method within a certain range,which would lead to the increase of its magnetic parameters M_(s)and H_(c).And the crystallinity was not the single factor affecting M_(s)and H_(c),the radial size of flaky particles also had obvious effects on M_(s)and H_(c).