Structural and magnetic properties of M-Ti (M=Ni or Zn) co-substituted M-type barium ferrite by a novel sintering process

摘要: M2+ (Ni2+ or Zn2+) ion together with Ti4+ were substituted for two trivalent Fe3+ ions of M-type barium ferrite in the form Ba(MTi)xFe12−2xO19 (x = 0.30, 0.60, 0.90 and 1.20). Samples prepared by solid state reaction sintered a novel process. The samples sintering process at high temperature 1175 °C 6 h slowly downed to 800 °C rate 1 °C per 1 min, then cooled air. This could control contract deformation grains effectively reduce pore formation. Under process, x = 0.30–1.20, co-substitution M–Ti caused no change single phase structure, exhibited more homogeneous microstructure. bulk density (ρ) increased Zn–Ti contents, maximum was 4.75 g/cm3 (x = 1.20), which 89.7 % theory (5.29 g/cm3). Magnetic properties such as saturation magnetization (M s ) coercivity (H c decreased increasing contents. permittivity first, different x content under Ni–Ti substitution.