Plating of Cu and Ni metals on Mg-ferrite sintered bodies by an electroless method and an investigation of magnetic behavior

摘要

Abstract MgFe~(2)O~(4)nanoparticles were synthesized using sol–gel autocombustion method. The structural and phase formation of the samples were studied through X-ray diffraction patterns. The results indicated that the MgFe~(2)O~(4)phase was formed along with a second phase of Fe~(2)O~(3)in the calcinated temperatures up to 900 °C. The desired single phase was produced by elevating calcination temperature to 1000 °C for 2 h. This is further confirmed by Fourier transform infrared spectroscopy, showing two absorption bands corresponding to the vibration of tetrahedral and octahedral complexes at ~ 570 and ~ 430 cm_(−1), respectively. The microstructure and morphology of the samples were studied using scanning electron microscopy; exhibiting even and rectangular-shaped particles with the average size of 270 nm. In the second stage, the 1000 °C—calcinated powders were pressed under 500 MPa and subjected to sintering from 1350 to 1500 °C with 50 °C increments for 1 h. The bulk density of the sintered bodies increased from 3.9 (at 1350 °C) to 4.25 g/cm_(3)(at 1500 °C) and the theoretical porosity reduced from 18.85 to 7%, respectively. Studying their magnetic properties, through a permagraph loop tracer, revealed that the saturation magnetization (M~(s)) increased from 1200 to 1420 G and the intrinsic coercivity (H~(cJ)) declined from 50 to 12 Oe, respectively. By plating of Cu and Ni metals on the 1500 °C—sintered body samples revealed that the M~(s)value, however, remained constant, the H~(cJ)reduced from 12 to 8 Oe, as compared to the 1500 °C—sintered body sample, which enable them promising candidates as inductor and transformer materials for high frequency applications.