Bi2O3 enhances magnetic and dielectric properties of low temperature co-fired Ba(CoTi)1.20Fe9.6O19 ferrite composites in an oxygen atmosphere for applications in high frequency antennas. (January 2018)

• Record Type: Journal Article
• Authors: Gan, Gongwen; Zhang, Huaiwu; Li, Qiang; Li, Jie; Li, Mingming; Xu, Fang; Jing, Yulan
• Is Part Of: Materials research bulletin. Volume 97(2018)
• Page Start: 37
• Page End: 41
• Publication Date: 2018-01
• Subjects: M-type barium ferrite -- Bi2O3 additive -- Magnetic permeability -- Dielectric permittivity; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2017.08.007
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Bi2O3 enhances magnetic and dielectric properties of Ba(CoTi)1.20Fe9.6O19 ferrite composites. Under an oxygen atmosphere condition, the magnetic and dielectric properties were increased obviously. The materials possessed equivalent real permeability and real permittivity. The materials possessed low magnetic loss and ultra low dielectric loss at high frequency. Abstract: M-type barium ferrites Ba(CoTi)1.20 Fe9.6 O19 were synthesized with 5.0 wt% Bi2 O3 additive at low temperatures in an oxygen atmosphere. For temperatures increasing from 900 °C to 945 °C, the saturation magnetization ( M s ) increased first and then decreased. However, coercivity ( H c ) decreased first and then increased. Superfluous Bi2 O3 produced BiFeO3 dielectric phase with Fe 3+ ions. When the samples were processed in an oxygen atmosphere, the magnetic and dielectric properties were obviously increased, in particular, the real permeability (μ′) and real permittivity (ε′). The processed materials exhibited nearly equivalent real permeability and real permittivity (at 935 °C, μ′ ≈ ε′ ≈ 20.6), and had low magnetic loss (tan δ μ ≈ 0.05) and low dielectric loss (tan δ ε ≈ 0.004) at the frequency of 100 MHz. The results showed the Bi2 O3 enhanced M-type barium ferrite was an excellent substrate material for high frequency antenna applications.