Structural and magnetic properties of Co2+-W4+ ions doped M-type Ba-Sr hexaferrites synthesized by a ceramic method

The Co2+ and W4+ ions (x) doped M-type hexagonal Ba0.5Sr0.5CoxWxFe12-2xO19 (x = 0.2, 0.4, 0.6, 0.8 and 1.0) ferrite compositions were prepared by a standard ceramic method. The crystal structure was identified with X-ray diffraction and grain morphology was explored with scanned electron micrographs (SEM). Vibrating sample magnetometer was used to examine the hysteresis loops and magnetic parameters were calculated from the same loops. XRD analysis confirmed the existence of M-type and Spinel phases of the synthesized compositions. SEM images and hysteresis loops of all compositions showed multidomain particles. The coercivity decreased and anisotropy field increased with doping of Co2+-W4+ ions from composition x = 0.2 to 1.0 whereas saturation magnetization and remanent magnetization first decreased from x = 0.2 to 0.8 and then both parameters increased in x = 1.0. The low coercivity and retentivity along with the tunable anisotropy field suggest for recording and microwave absorber applications. (C) 2016 Published by Elsevier B.V.