UNIVERSIDADE ESTADUAL DE MARINGÁ - Pfi.uem.br

Abstract<br />
Multiferroic magnetoelectric materials have attracted much attention of<br />
the theoretical and experimentalist researchers because they can present, in<br />
the same phase, ferroelectric and magnetic orderings. Among them, BiFeO3 is<br />
one of the most promising candidate for practical applications, whereas it<br />
presents high ferroelectric and antiferromagnetic ordering temperatures. The<br />
high electrical conductivity and the low dielectric permittivity are the main<br />
problems of working with BiFeO3, beyond the difficult for obtaining single<br />
phased materials. For solving these problems, process BiFeO3 with others<br />
perovskite structured materials that present high dielectric permittivities, like<br />
PbTiO3 and BaTiO3, seems to be an adequate alternative.<br />
Taking in mind this assumptions, in this work we processed, by<br />
high-energy ball milling, samples of the (x)BiFeO3-(1-x)BaTiO3 system, with 0,9<br />
≥ x ≥ 0,6, focusing the improvement of the BiFeO3 ferroic properties. The<br />
structural and microstructural characterizations had showed the formation of<br />
single phase perovskite structured materials. These samples have<br />
predominantly the R3c space group. The mean particle sizes of powders<br />
reached the nano scale, while the ceramics presented high densification rates<br />
with relatively homogeneous grains morphologies. All the processed materials<br />
showed antiferromagnetic and ferroelectric orderings at room temperature,<br />
which dielectric permittivities higher than that presented by the BiFeO3<br />
compound.<br />
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