Some magnetic properties of Li-Ga ferrite in low magnetic field

摘要

Li-gallium ferrites with the chemical formula Li_(0.5)GaxFe_(2.5-x)O_4 (x＝0.0.1,0-2, 0.3,0.4 and 0.5) have been prepared by the ceramic method technique. The spinel structure in homogenous state was realized by X-ray diffraction analysis. The lattice parameter was determined for each composition and it was found approximately constant value (0.832 ran). Some magnetic properties such as magnetization M, and (B-H) loop were measured at room temperature. The magnetization M was measured in the range of magnetizing field up to 800Am~(-1).rnThe B-H loops were measured at elevated temperature and magnetizing current (I＝1 A which is equivalent to 200 Am~(-1)). At room temperature the relative permeability(μ_r) was calculated from M-H relation. Also, remanence magnetization (M_r), saturation magnetization (M_s) and apparent loss energy (P_s) were estimated from B-H loops. It was found that μ_r, M_rr M_s and P_s are composition dependent. The initial permeability (μ_i) was measured as a function of temperature from room temperature up to 893 K. The Curie temperature T_C and paramagnetic temperatures (T_p and T_s) weredetermined. These values of temperature have been found to decrease with increasing Ga~(3+) content.