Analysis of structural and microstructure of lanthanum ferrite by modifying iron sand for microwave absorber material application

摘要

Analysis of crystal structure of lanthanum ferrite by modifying iron sand has been carried out. Lanthanum ferrite included one of the functional materials which had composition of ABO3 perovskite system. The lanthanum ferrite was prepared by iron sand and lanthanum oxide powders. The mixture was milled for 10h with the various composition of lanthanum content. The samples were sintered at a temperature of 1000 °C for10h. The microstructure analyses showed that the particle shapes were polygonal with the varied particle sizes and uniform distribution on the surface of the sample. The phase composition of refinement result showed that the lanthanum ferrite formed empirical compound of Lao.8Mgo.2Feo.7Tio.2Sio.1O3. The Lao.8Mgo.2Feo.7Tio.2Sio.1O3 phase has a structure orthorombic (P b n m) with lattice parameters a = 5.513(1) A, b = 5.549(1) A and c = 7.849(2) A, a = (3 = y = 90°, the unit cell volume of V = 240.2(9) A3, and the atomic density of p = 6.293 gr/cm3. We concluded that this study has successfully synthesized lanthanum ferrite material from modifying iron sand and has been understood changes in the parameters of the crystal structure and phase composition of this material. It is a great opportunity that the material could be used as a candidate material for absorbing electromagnetic waves.