Preparation and electromagnetic properties of SmCo_xFe_1-xO₃

SmCo_xFe_1-xO₃ (x=0, 0.2, 0.4, 0.6) powders were prepared by solid state reaction. The phase composition and surface appearance of the obtained SmCo_xFe_1-xO₃ ferrites were characterized by XRD, and SEM, respectively. Moreover, the electromagnetic properties and microwave reflection loss (RL) were measured using network analyzer (Agilent 8722ET). The results showed that the pure SmFeO₃ formed when x ≤ 0.4 at 1250°C for 3 h. In addition, the particles exhibited irregular shape. The particle size decreased with the increasing substitution amounts of Co and the average size was about 1μm when x=0.4. A small amount of Co substitution could adjust dielectric loss and complex permittivity. For the single SmCo_0.4Fe_0.6O₃ microwave absorber, the maximum reflection loss (RL) was about -21 dB at 15.8 GHz when the thickness was 2.1 mm.