Abstract
Considering that Ca2+ has the similar ion radius and the substituted ability as Sr2+ and Ba2+ but the same family, CaxSr1-x-yLayO•nFe(2n-z)/nCoz/nO3 ferrites have been synthesized by the conventional ceramic process. Structure and magnetic properties of CaxSr1-x-yLayO•nFe(2n-z)/nCoz/nO3 compounds have systematically been investigated by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM) and B-H hysteresis curve measurements. Several compositions are selected to investigate the formation of M phase with the joint replacement of Ca-La-Co. It is found that the formation mechanism is based on the replacement of Sr2+ by La3+ plus Ca2+ and the charge compensation by Co2+. In futher results, the unexpectedly intrinsic coercivity of 436 kA/m and residual flux density of 0.445 T were obtained. In terms of material preparation, we believe that CaxSr1-x-yLayO•nFe(2n-z)/nCoz/nO3 is effective in the production of future high energy permanent magnets.
Publisher
Trans Tech Publications, Ltd.
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