Influence of sintering process on the microwave dielectric properties of Bi(V0.008Nb0.992)O4 ceramics

Relationship between sintering process, relative density (shrinkage), grain morphological parameters and microwave dielectric properties of Bi(V0.008Nb0.992)O4 ceramics was studied. Influence of incubation time and sintering temperature on the microwave dielectric properties was discussed. The experiential logarithmic relationship and the parabola relationship were used to simulate the relationship between microwave permittivity, different incubation time and different sintering temperatures, respectively. Modification of Bosman and Havinga's correction was used to eliminate the influence of pores on the permittivity of ceramics. The experimental, calculated and modified results corresponded well with each other. Morphological parameters of grains and pores were found to have dominant influence on microwave dielectric loss and the qualitative relationship was given. The best microwave dielectric properties were obtained in ceramics sintered at 830 °C for 2 h with heating ratio of 3 °C min−1 with permittivity about 40 and Qf reaching 18,500 GHz while relative density was only about 93.5%.