Synthesis and study of the lanthanum substitution in the lead M-type hexaferrite Article uri icon

abstract

  • In this work we investigated the best conditions to obtain the lanthanum-substituted lead M-type hexaferrite using the ceramic method. In order to survey the solubility of lanthanum in the structure of the hexaferrite, we varied the molar fraction from 0.1 to 0.9. We performed a structural characterization using X-ray diffraction and used the Rietveld method to refine the crystal structure. The magnetic properties were obtained using vibrating sample magnetometry, and the microstructural characteristics were analyzed using scanning electron microscopy. The results indicate that the crystal structure of the hexaferrite is preserved with a substitution up to 70 %25∈mol of lanthanum. Moreover, the magnetic characterization exhibits a complicated behavior of parameters when lanthanum concentration increases, which can be attributed to the change of valence state of some iron cations that arises from lanthanum substitution in the hexaferrite; even more, the coercivity presents a drastic fall leading to consider these hexagonal ferrites as magnetically soft. © 2014 Springer Science%2bBusiness Media New York.

publication date

  • 2014-01-01