Electromagnetic Properties of YIG Polycrystalline Ceramics Fabricated by Tape-casting Method

Pure phase Y3Fe5O12 (YIG) ceramic was successfully produced by tape-casting forming process and one-step solid-state sintering method. The activation energy for densification was calculated to be 183.81 kJ/mol. Pure YIG ceramic with a relative density as high as 99.8% was fabricated. The existence of 0 vacancy and Fe2+ ions was determined by XPS and EPR spectra. The RT saturation magnetization was measured to be 28.2 emu/g, and the hysteresis loss was calculated to be smaller than 10 mJ/kg in the temperature range of 230 similar to 360 K and be as high as 238.8 mJ/kg at 30 K. The dielectric loss tangent tan delta(epsilon) was nearly zero at 6 similar to 7 GHz and 11 similar to 12 GHz. For complex permeability in the frequency range of 5 similar to 18 GHz, the magnetic loss tangent tan delta(mu), fluctuated at around zero. Therefore, the low values of tan delta(epsilon) and tan delta(mu), indicate that it is a low loss ceramic material.