Structural and Magnetic Properties of Nanosized Barium Hexaferrite Powders Obtained by Microemulsion Technique

Abstract

Abstract. Thin hexagonal barium hexaferrite particles synthesized using the microemulsion technique were studied. A water-in-oil reverse microemulsion system with cetyltrimethylammonium bromide (CTAB) as a cationic surfactant, n-butanol as a co-surfactant, n-hexanol as a continuous oil phase, and an aqueous phase were used. The microstructural and magnetic properties were investigated. The particles obtained were mono-domain with average particle size 280 nm. The magnetic properties of the powder were investigated at 4.2 K and at room temperature. The saturation magnetization was 48.86 emu/g and the coercivity, 2.4 x 10 5 A/m at room temperature. The anisotropy field H a and magneto-crystalline anisotropy K 1 were 1.4 x 10 6 A/m and 2.37 x 10 5 J/m 3 , respectively.

Physical and Morphological Properties of Hard- Soft Ferrite Functionally Graded Materials

“…(10a) the grain morphology appear totally plate -like shape which is clearly indicated the formation of barium ferrite. Barium hexaferrite nanoparticles with plate-like morphology is the best for the electromagnetic wave absorption application [9]. Also for the composite layer SEM images show the grain microstructure as a combination of spherical and plate like structure which is an evidence for the gradation in FGMs samples and resulting in properties variation.…”

Topical Review: Progress and Prospects of Hard Hexaferrites for Permanent Magnet Applications

“…Water-in-oil microemulsions have also been applied to prepare single domain M-type hexaferrite particles. Koutzarova and coworkers used a reverse microemulsion containing cetyltrimethylammonium bromide as cationic surfactant, n-butanol as co-surfactant, n-hexanol as a continuous oil phase, and water to obtain, after a calcination step at 900 • C, pure Baferrite nanoparticles with average size 280 nm [103]. Most of the particles were found to have an almost perfect hexagonal shape with average aspect ratio diagonal/thickness of 7.7, although the smallest ones (ca.…”

Synthesis and characterization of barium hexaferrite with manganese (Mn) doping material as anti-radar

“…It is suggested that a combination of dopants can be used to control or to reduce the coercivities with only a small change of their saturation magnetizations. Thus, the substitutions of Fe ions by isovalent cations can be generally investigated BaM constituent element iron can be replaced by other metal cations from the group of transition which has almost the same size as Co, Zn, Ni and Mn [5]. This study concentrates synthesis of barium hexaferrite by doping Mn with the variable value x = 0; 0.2; 0.4; and 0.6 and calcinations at 400, 600, and 800 0 C. Furthermore characterization of barium hexaferrite powder with doping to determine the changes that occur after being given additional element Mn dopants and calcinations temperature.…”