Resumo

PRIETO, FRANCISCO; GORDILLO, ALBERTO; RIVERA, EURIDICE  e  MENDEZ, MARÍA A.. NICKEL FERRITE SYNTHESIS AND EVALUATION OBTAINED BY MECANOSÍNTESIS AND THEIR COMPARISON WITH MANGANESE FERRITE. Dyna rev.fac.nac.minas [online]. 2009, vol.76, n.158, pp. 55-68. ISSN 0012-7353.

The objective of this work has been to evaluate by comparison, the characteristics of Mn and Ni ferrites that have been obtained starting of their basic oxides by via mechanosynthesis. The process was carried out to room temperature, in vacuum; like milling means steel spheres of 3 mm of diameter and cylindrical bottles of 50 cm³ of capacity of the same material; relation in weight of ball/dusts of 10:1. The maximum time of the process was of 12 hours. They were evaluated by XRD, AAS, FTIR, SEM and magnetic permeability and distribution and sizes of particles. The obtaining of this ferrites by via mecanosíntesis is effective but not from greater purities or homogeneities than the obtained by hydrochemical way. The most efficient time of the process it oscillates between the 7-10 hours of milling, slightly smaller for the manganese ferrite. Greater molar fraction is obtained (0,90) in the manganese ferrite in relation to the one of nickel; they were not significantly homogenous. In values of magnetic permeability the manganese ferrite was superior like in sizes of particles.

Palavras-chave : Mechanochemistry; Phases; Ferrites; Magnetic Permeability.