Low-temperature Sintered Y-type Hexagonal Ferrites with High Permeability

摘要

Low-temperature sintering Y-type hexagonal ferrites were made by the ceramics method. The temperature obtaining a single phase shifted lower with the CuO content. In Ba_2Co_(1.0)Cu_(1.0)Fe_(12)O_(22), a single phase was obtained at 950 deg C calcination. At the same time, the shrinkage curve shifts to the low temperature, and the faring temperature that is able to get over 95 percent of the theoretical density has lowered from 1200 deg C to 1000 deg C by the CuO substitution. Further more, Bi_2O_3 addition shifted the shrinkage curve to the low temperature. Exact sintered body with 900 deg C sintering was obtained by 5 wt percent addition. The permeability and resonance frequency were 2.3 and 5.7GHz respectively. The permeability was improved by divalent metal substitution, Ba_2Me_(1.0)Cu_(1.0)Fe_(12)O_(22) (Me: Ni,Mg,Zn), and the highest permeability was achieved by Zn substitution. The permeability and resonance frequency were 9.7 and 1.0GHz respectively. It is found that Ba_2Zn_xCu_(2-x)Fe_(12)O_(22) with Bi_2O_3 addition show high performance as magnetic material for chip inductors.