Abstract
Nanoparticles CrxAl0.5-xCoFe1.5O4 (x = 0.1, 0.25 and 0.4) spinel ferrites were synthesized by co-precipitation technique, aiming to study the relationship between cation distribution of the substitution of chromium and aluminum ions on the structure, morphology, magnetic properties, permeability, Curie temperature and AC loss. X-ray diffraction (XRD) analysis used with Rietveld refinement revealed nanocrystalline single-phase of the spinel ferrites. The calculated average crystallite size is between 40 and 45 nm. The obtained results show, that both lattice constant and total porosity increased by increasing Cr3+ concentration. It was found that Al3+ occupied tetrahedral (A) and octahedral (B) sites whereas, Cr3+ preferred to occupy only octahedral (B) sites. The magnetization M-s,M- coercivity H-c and the magneto-crystalline constant k(1) decreased with increasing Cr3+ content. Likewise, Curie temperature T-C decreased from 670 K to 585 K with increasing Cr3+ concentration. Magnetic loss has further been observed and increased with increasing Cr3+ concentration in all investigated samples.