Influence of Co₂O₃ additive on electromagnetic properties of NiCuZn/CaCu₃Ti₄O₁₂ composites

Abstract

  In order to improve the electromagnetic properties of 80wt%NiCuZn + 20wt% CaCu₃Ti₄O₁₂ composites, Co₂O₃ as an additive was studied in this work. The effects of Co₂O₃ content on the electromagnetic properties were investigated, which confirmed that permeability of composites was decreased and cut-off frequency was improved with Co₂O₃. The nonlinear fitting of permeability dispersion have revealed the relationships between domain wall resonance, spin rotation relaxion mechanisms, and local induced anisotropy, the existence of local induced anisotropy caused by ordering of Co ions could influence the initial permeability. Meanwhile, the dielectric constant was increased with the addition of Co₂O₃, and all the samples kept a lower tanδ，which was less than 0.01 at the frequency between 10⁷Hz to 10⁸Hz.