Abstract: The xLi_0.5Bi_0.5MoO₄-(1-x)Li₂Zn₂(MoO₄)₃ [xLBM-(1-x)LZM] composite ceramics were prepared by traditional solid-state reaction method. The sintering characteristics, phase composition, microstructures and microwave dielectric properties of LZM ceramics with different mass fraction (x=25%, 30%, 35%, 40% and 45%) of LBM were investigated. The results show that, LBM effectively adjust the resonant frequency temperature coefficient (τ_f) of LZM ceramics to near zero and also decreases the sintering temperature; LBM can coexist with LZM, and no new phases are detected in addition to the LZMT and LBM phase. With the increase of LBM ceramics, the sintering densification temperature decreases gradually, the bulk density of composite ceramics initially increases and then decreases, the permittivity (ε_r) and τ_f increases, the quality factor (Q×f) decreases gradually. When 40%LBM ceramics is added, LZM-LBM composite ceramics sintered at 600 ℃ for 2 h obtained maximun bulk density of 4.41 g/cm³,and excellent microwave dielectric properties of the ε_r is 13.8, the Q×f is 28 581 GHz and τ_f is -5×10^-6/℃.

Key words: Li_0.5Bi_0.5MoO₄ ceramics, Li₂Zn₂(MoO₄)₃ ceramics, low temperature sintering, microwave dielectric property