Authors : M. N. Giriya, C. L. Khobaragade, D. S. Bhowmick, K. G. Rewatkar and R. P. Tandon
Page Nos : 334-339
Description :
Abstract:
Ca-Sr hexaferrite samples with chemical composition Ca0.5Sr0.5MexFe12-2xO19 where (x = 0, 0.5,1) and (Me = CoTi) synthesized using proper stoichiometric proportions by solid state reaction at 1040oC for 105 hr. The chemical phase analysis has been carried out by X-ray powder diffraction (XRD) method, which confirms the formation of the ferrite structure. It shows hexagonal magnetoplumbite (M) type structure having unit cell dimension ‘a’ and ‘c’ varies between 5-6 Ǻ and 21-23 Ǻ. Coercivity (Hc), saturation magnetization (Ms), Retentivity (Mr) and Bohr magnetron (ηB) measurements were carried out on a vibrating sample magnetometer (VSM) with an applied field up to 10 KOe. The results were explained in the light of Gorter’s (1957) spin model. The magnetiza-tion results indicate that the Al+3 ions preferentially occupy the 2a, 12k, and 4f2 sites. This confirms the use of samples in the various applications of digital data storage devices.
Keywords: X-ray density, porosity, magnetization, coercivity, retentivity etc.
