Effect of microstructural evolution from nano to micron grain size regime towards structural, magnetic, electrical and microwave properties of gadolinium iron garnet (Gd_3Fe_5O_(12))

摘要

The influence of microstructural changes from nano to micron grain size regime towards their structural, magnetic, electrical and microwave properties of gadolinium iron garnet (Gd_3Fe_5O_(12)) has been investigated systematically in this research work. Raw materials were milled via high-energy ball milling (HEBM) followed by subsequent sintering (600-1400 °C) process. X-ray diffraction (XRD) analysis had shown that single phase with garnet structure and highest crys-tallinity of Gd_3Fe_5O_(12) was formed at 1000 °C. The B-H hysteresis loop unveil the evolution development of magnetic behaviour (paramagnetism-ferrimag-netism) in samples thru variation of different sintering temperature. The values of linewidth (ΔH) can be grouped into two groups which are; sample increased from 600 to 1000 °C due to shape and strain induced anisotropy while decreasing from 1100 to 1400 °C influenced by magnetocrystalline anisotropy with the increment of the sintering temperature.