Low temperature sintered of Ba3MgNb2O9 ceramics with high quality factor via B-site oxide precursor method

B-site oxide precursor method was utilized to synthesize Ba 3 MgNb 2 O 9 ceramics. The effects of sintering temperature on phase composition of Ba 3 MgNb 2 O 9 ceramics was evaluated by the X-ray diffraction. Experimental results indicated that all prepared Ba 3 MgNb 2 O 9 ceramics exhibited 1:2 ordered hexagonal structure. The second phase Ba 5 Nb 4 O 15 can emerge in all ceramics due to the decrease of activation energy of reaction, leading to the splitting of E g (O) vibration mode in the Raman spectra. In addition, lattice parameters of 1:2 ordered phase were obtained from the refinement of XRD patterns. The maximum value of c/a ratio occurred at 1475 °C, meanwhile the ceramics showed the highest 1:2 ordered degree and excellent Q × f. It was also found that the uniform grain-size distribution of Ba 3 MgNb 2 O 9 powder were important factors for preparing dense Ba 3 MgNb 2 O 9 ceramics. Moreover, B-site oxide precursor method can not only effectively lower the densification temperature from 1650 to 1475 °C, but also increase the quality factor ( Q × f ) by about 90.8%, i.e., from 55,277 to 105,467 GHz.