Suresh S. Darokar
In the present investigation, the series of aluminium and cobalt substituted lithium hexaferrites with chemical compositional formula Li0.5Fe0.5+xAl12-2X CoX O19 (where x=2,3,4,5 and 6) was synthesized using perfect stoichiometric mixtures of oxide by standard ceramic solid state reaction method at 12000C for 120 hrs. The chemical phase analysis of all compounds has been checked by X-ray powder diffraction (XRD) which confirmed the formation of the ferrite structure. It shows all are hexagonal magnetoplumbite (M -type) structure without traces of uncertainly ambiguous reflection having unit cell dimension ‘a’ in the range from 5.6953 A.U to 5.8594 A.U and ‘c’ varies between 21.2626 A.U to 22.3234 A.U pertaining the space group P63/mmc (No.194). The mass density of the ferrites were found linearly varies and depends upon the mass and volume of sample. The magnetic properties of polycrystalline sample are studied by using the external applied magnetic field up to 10 KOe and it shows the moderate values of coercivity (Hc), saturation magnetization (Ms) and retentivity (Mr).This measurements were carried out on a vibrating sample magnetometer (VSM).