The Magnetic Properties Of Iron Zinc Ferrites

Hydrothermally synthesized rare-earth oxide compounds such as Nd2O3, Dy2O3, Gd2O3, Eu2O3, Y2O3, etc. and hydroxide compounds such as Y(OH)3, Dy(OH)3, Gd(OH)3, Eu(OH)3, Tb(OH)3, etc. have been widely used as high-performance luminescent devices, catalysts and other functional materials based on the electronic, optical and chemical characteristics arising from their 4f electrons. In the crystallization process, surfactant molecules adsorbed on the crystal nuclei serve not only as a growth director but also as a protector to prevent from aggregation of the product. As a result, nanorods were produced. Cetyl trimethyl ammonium bromide (CTAB) and hexadecylamine (HDA) surfactant are plays a key role in controlling the growth and production of oxide phosphors in the hydrothermal method.

The relations between the mechanical and magnetic properties of a ferrite are derived for the small signal or reversible condition using thermodynamic principles. The equation of motion of a ferrite ring driven in its fundamental mode is set up and solved leading to the equivalent electrical circuit of the magnetostriction resonator. From mechanical measurements of the density and dimensions of the ring and electrical and frequency measurements of the resonator, the elastic modulus, permeability, magnetostriction coefficients and loss factors in the ferrite can be determined. Apparatus is proposed for performing the above measurements.

Doctoral Thesis / Dissertation from the year 2010 in the subject Physics - Nuclear Physics, Molecular Physics, Solid State Physics, Dr. Babasaheb Ambedkar Marathwada University (-), course: PH.D., language: English, abstract: Wide scope is available to study these aspects of ferrite which at present to our knowledge was not probe by researchers. In relevance to the ever expanding possibilities, and potential that is available with the ferrite materials, the scope of presently undertaken work is designed carefully by selecting suitable ferrite and dopants. A sincere attempt was made to extract fruitful, exhaustive and, systematic information regarding structural, cation distribution, electrical, dielectric and magnetic aspects of the ferrite systems under investigations. In the present study, the properties of nickel ferrites substituted by diamagnetic Zn2+, non-magnetic trivalent In3+ ions and tetravalent Ce4+ ions are studied for various compositions. The properties are investigated with a view to understand the effect of divalent, trivalent and tetravalent substitution in nickel ferrite. The thesis consists of five chapters. Chapter 1 related to Scope, problem statement, theory of magnetism, ferrites, background, motivation and aim of the present work, properties of the samples under investigations, objective and outline of thesis. Chapter 2, 3 and 4 related to results and discussion of structural, electrical and magnetic properties of Ni1-xZnxFe2O4, NiInxFe2-xO4 and Ni1-2xCexFe2O4 ferrite system respectively. Chapter 5 gives the summary, discussion and conclusion on Zn, In and Ce substituted nickel ferrite. On summarizing the results obtained on Ni-Zn, Ni-In and Ni-Ce spinel ferrites it can be concluded that; - The structural properties are found to be varying in all the three systems. The lattice parameter of Ni ferrite systems increases with increasing valancy of dopants (Zn2+, In3+ and Ce4+). - The other prominent parameter of our structural study i.e. p