Study on microwave properties of low temperature fired NiZnCu gyromagnetic ferrite

Abstract

This paper describes the microwave properties of low temperature fired Ni0.6CuxZn(0.4−x)Fe1.96+δO4 gyromagnetic ferrite material synthesized by conventional oxide process with Bi2O3 additives. It is found that 60–63 mol % Ni and 5 mol % Cu contents have the advantage to keep the material with both low-fired characteristic and high saturated magnetization with 3 wt % Bi2O3 additives. Considering the conditions of milling, calcination, and sintering process, the low temperature fired NiCuZn gyromagnetic material was prepared with excellent microwave performances. The saturated magnetization Ms of the sample is 337 kA/m, the ferromagnetic resonance linewidth ΔH and dielectric loss tgδε less than 16 kA/m and 5.7×10−4, respectively, which has the potential applications for low temperature cofired ceramics technology to develop microwave chip circulator/isolator and passive integrated substrate.