Influence of different milling time on synthesized Ni–Zn ferrite properties by mechanical alloying method

Abstract

The main issue in this study was to investigate the effect of milling time on the synthesis of nickel–zinc ferrite by mechanical alloying method by parameter optimization approach and achieving nickel–zinc ferrite with high saturation magnetization and low coercivity. For the synthesis of nickel–zinc ferrite, nickel, zinc and iron oxides were milled in different proportions by planetary ball milling. To investigate the effect of milling time, sampling was performed every 2.5 h to 10 h and then every 10 h to 40 h. To prevent agglomeration of the particles and reduce their surface energy, deionized distilled water was used as the milling media. After completion of milling, the samples were dried in air. To complete the synthesis process, the powders were first calcined at 900 °C for 5 h and then sintered at 1200 °C for 3 h in the high-temperature furnace. Samples from each step were characterized by an X-ray diffraction test, which showed an increase in the amount of ferrite synthesized with increasing milling time. The Fourier-Transform Infrared Spectroscopy (FTIR) test according to the peaks at the wavelengths of 1100 cm−1 and 1600 cm−1 confirmed the existence of nickel–zinc ferrite. Magnetic sample vibration test (VSM) investigated the optimum sample (40 h milled) magnetic properties and its saturation magnetization, residual magnetization, and coercivity were 54 A m2/kg, 1 A m2/kg, and 1.99 × 103 A/m, respectively. The particle size and morphology of nickel–zinc ferrite particles were investigated using Field Emission scanning electron microscopy (FESEM) and the average particle size of the optimum sample was ~ 41 nm. This result is confirmed by particle size distribution (PSA).