Microwave sintering of (Bi0.75Ca1.2Y1.05)(V0.6Fe4.4)O12 microwave magnetic materials

Microwave sintering (ms) process is applied to efficiently densify the (Bi0.75Ca1.2Y1.05)(V0.6Fe4.4)O12, Bi-CVG, materials, without inducing a deleterious effect on their microwave magnetic properties. A microwave sintering process can sinter the Bi-CVG materials to a density as high as 96.5%T. D., by firing the samples at 1030 °C (30 min). In contrast, it needs 1060 °C (6 h) to densify the materials to the same high density by a conventional sintering (cs) process. The ms-processed Bi-CVG materials possess pronouncedly smaller grain size (∼1.2 μm), which markedly hinders their low frequency magnetization process (in a few tens of MHz frequency regime), resulting in larger coercive field (Hc) and smaller initial permeability (μi), as compared with the cs-processed large grain samples. But such a small grain characteristic insignificantly degrades the microwave magnetic properties, the resonance line width (ΔH), of the Bi-CVG materials.