Effects of pH value and Sintering Temperature on the Structural and Magnetic Properties of Barium Hexaferrites Prepared by Co-Precipitation

Barium hexaferrite (BaFe12O19; M-type; BaM) is an important, cost effective magnetic material for permanent magnet applications. The properties of the prepared samples, and purity BaM phase depend critically on synthesis route experimental conditions. In this study, hexaferrites were by co-precipitation method using two different values pH precursor solutions (11.0 12.5), sintering pellets co-precipitates at 860, 920 990°C.The samples characterized X-ray diffraction measurements. patterns indicated that with = 12.5 consisted a single all temperatures. However, 11.0 did not reveal existence 860°C, whereasa major (86 – 87 wt.%) was observed 990°C minor ?-Fe2O3 phase. thermo curves confirmed in samples. hysteresis loops showed characteristics hard materials relatively high saturation magnetization. Analysis data intrinsic coercivity Hci~ 5 kOe specific magnetization range ?s 56.0 66.3 emu/g, which are suitable practical (HcB), residual induction (Br) maximum energy product (BH)max higher than those 11.0, highest parameters HcB 1871 Oe, Br 2384 G, 8.92 kJ/m3 sample sintered 860°C.