Modifications in structural, cation distribution and magnetic properties of Co-60 gamma irradiated Li-ferrite

作者：Mane Maheshkumar L; Shirsath Sagar E^*; Dhage Vinod N; Jadhav K M

来源：Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms , 2011, 269(18): 2026-2031.

DOI：10.1016/j.nimb.2011.06.005

• Ferrites
• Gamma irradiation
• Cation distribution
• Diffusion coefficient
• Dielectric constant

Polycrystalline samples of Li0.5Fe2.5O4 ferrite precursor were prepared by conventional standard double sintering ceramic technique and then irradiated with three different doses of Co-60 gamma rays. The crystal structure and phase orientation of the irradiated and unirradiated samples of Li0.5Fe2.5O4 ferrite was done by using X-ray diffraction technique at room temperature. The lattice parameter of the studied samples increased due to the formation of Fe2+ ions under the ionizing effect of gamma radiation. The strain in the materials due to the irradiation was calculated from XRD data. Scanning electron microscope (SEM) studies indicate that the irradiation causes amorphization, especially at the grain boundaries. The cation distribution was calculated from XRD data analysis. By using cation distribution structural parameters such as theoretical lattice constant, ionic radii of available sites and the oxygen parameter 'u' have been calculated. The estimated cation distribution and other structural parameters shows strong influence of gamma rays on polycrystalline Li-ferrite. The magnetic properties of irradiated and unirradiated lithium ferrite were performed by using pulse field hysteresis loop technique at room temperature. Electrical properties such as diffusion coefficient and dielectric properties were carried out with the influence of gamma irradiation. Activation energy of diffusion process decreased after irradiation. The increase of diffusion coefficient with increasing dose rate of gamma irradiation was reinforced by the increase of Fe2+ ions and the displacement of metal ions from its original sites under the effect of gamma irradiation.

• 出版日期2011-9-15