Cobalt ferrite magnetic properties

The spinel ferrites were fabricated by solid state reaction technique. Cobalt and Zinc ferrites CoxZnyFe204,(x=0.7,0.3,0.4,0.2 and y=0.3,0.7,0.6,0.8) were prepared by solid state reaction technique. The crystalline structure of the sample was investigated by X-ray diffraction(XRD). All samples show cubic spinel structure. The lattice parameter decreases with increasing cobalt content. Magnetic properties shows that the prepared sample exhibit ferromagnetic behaviour at room temperature. The saturation magnetization increases with increasing cobalt content. Curie temperature... 

Study of Magnetic Properties of Mixed Cobalt-Zinc Ferrites Synthesized By Solid State Reaction Technique. 

Hydrothermal Method. Iron [Fe(III)], barium, and the dopants are precipitated as their hydroxides and reacted with an excess of sodium hydroxide solution (up to 6 mol/L) at 250-350 °C in an autoclave. This is generally followed by an annealing treatment at 750-800°C to obtain products with the desired magnetic properties. Many variations of the process have been described [5.36]-[5.40], the earliest report being from 1969 [5.41], In later processes, hydrothermal synthesis is followed by coating with cubic ferrites, a process resembling the cobalt modification of iron oxides (see Section 5.1.2). The object is to increase the saturation magnetization of the material [5.42]-[5.44],... 

Prabhat K. Srivastava, G. P. (1988). Dielectric and magnetic properties of polycrystalline cobalt-substituted LiTi ferrites. Journal of Applied Physics, 63, 3780-2. 

At the end of the 1960s, a new material with exceptional hard magnetic properties (Table 6.7) was prepared samarium-cobalt, SmCoj. Its most outstanding property is its magnetocrystalline anisotropy reported values are in the range (11-20) x 10 J/m (by comparison, Ba ferrite has an anisotropy of 0.33 x 10 J/m, Table 4.15). Rather than being a serendipitous discovery, the successful synthesis of SmCoj was the result of a systematic effort (Strnat, 1988). 

Moumen, N., Pileni, M.P New syntheses of cobalt ferrite particles in the range 2-5 nm comparison of the magnetic properties of the nanosized particles in dispersed fluid or in powder form. Chem. Mater. 8, 1128-1134 (1996)... 

Hochepied, J.F., Pileni, M.R Magnetic properties of mixed cobalt-zinc ferrite nanoparticles. J. Appl. Phys. 87, 2472-2478 (2000)... 

N. Sivakumar, A. Narayanasamy, K. Shinoda, C.N. Chinnasamy, B. Jeyadevan, J.-M. Greneche, Electrical and magnetic properties of chemically derived nanocrystalline cobalt ferrite. J. Appl. Phys. 102, 013916 (2007)... 

AT Ngo, MP Pileni. Nanoparticles of cobalt ferrite influence of the applied field on the organization of the nanocrystals on a substrate and on their magnetic properties. Adv Mater 2000 12 276. 

CNTs are a prospective novel material for multi-component nano-composite fibers, as they have been widely applied as composites components because of their excellent optical, mechanical, and electrical properties. Cobalt ferrite (CoFe204) nanoparticles are an important magnetic material used in high-density data storage, ferrofluids, and electronic devices. ... 

Sangmanee M, Maensiri S (2009) Nanostructures and magnetic properties of cobalt ferrite (CoFe204) fabricated by electrospinning. Appl Phys A 97(1) 167-177. doi 10.1007/s00339-009-5256-5... 

Soft magnetic materials are characterized by high permeabiUty and low coercivity. There are sis principal groups of commercially important soft magnetic materials iron and low carbon steels, iron—siUcon alloys, iron—aluminum and iron—aluminum—silicon alloys, nickel—iron alloys, iron-cobalt alloys, and ferrites. In addition, iron-boron-based amorphous soft magnetic alloys are commercially available. Some have properties similar to the best grades of the permalloys whereas others exhibit core losses substantially below those of the oriented siUcon steels. Table 1 summarizes the properties of some of these materials. 

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