Magnetic and dielectric properties of Sm-doped M-type barium ferrites for LTCC application

摘要

In this study, Sm-doped M-type barium ferrites (BaFe12-xSmxO19, x = 0.0 to 0.8 with a step of 0.2) were prepared by traditional solid state method at low temperature (~920°C) with sintering aids. XRD showed that Sm-doped into M-type barium ferrite had no other phase formation. SEM showed that the grain size increased from 1μm to 2μm with Sm-doped. In magnetic properties, magnetization hysteresis loops (M~H) were measured using VSM equipment (Vibrating Sample Magnetometer). With Sm contents increasing, and saturation magnetization (Ms) decreased from 47.5 emu/g to 27.6 emu/g, and the coercivity (Hc) first decreased from 4156 Oe (x=0.0) to 3688 Oe (x=0.4) and increased to 3843 Oe (x=0.8). For dielectric properties, the real part permittivity (ε') increased kept a stable value from 15 to 33 in a range frequency of 10 MHz-500 MHz, and kept a low dielectric loss. Hence, these ferrite materials are expected to be applied in many applications on electronic devices field.