低温烧结Mg_4Nb_2O_9-0.75wt%V_2O_5-1.5wt%Li_2CO_3微波介质陶瓷及其性能研究

Low Temperature Sintering and Property of Mg_4Nb_2O_9-0.75wt%V_2O_5-1. 5wt%Li_2CO_3 Microwave Dielectric Ceramics

采用高能球磨法制备陶瓷,研究了0.75wt%V2O5和1.5wt%Li2CO3共掺杂对Mg4Nb2O9陶瓷的烧结性能和微波介电性能的影响。实验结果表明0.75wt%V2O5和1.5wt%Li2CO3共掺杂有助于Mg4Nb2O9陶瓷在烧结过程中形成液相,促进低温致密化烧结,进而降低陶瓷的烧结温度。900℃烧结Mg4Nb2O9陶瓷,结构致密、组织均匀,平均粒径0.75μm,εr=12.58,Q×f=5539 GHz。随烧结温度升高,晶粒长大,密度升高,εr和Q×f值增大。微波介电性能表征表明Mg4Nb2O9-0.75wt%V2O5-1.5wt%Li2CO3陶瓷在950℃下低温烧结,获得εr=13.07,Q×f=10858GHz的亚微米级陶瓷,其优良的微波介电性能使其有望成为新一代低温烧结低介高频微波介质基板材料。

Mg4Nb2O9 ceramics were obtained by using the high energy ball milling method. Meanwhile, the effects of doping of 0.75wt% V2O5 and 1.50wt% LiECO3 on the sintering behavior and microwave dielectric properties of Mg4Nb2O9 ceramics were investigated. Experimental results showed that doping of 0.75wt% V2O5 and 1. 5wt% Li2CO3 helped form a liquid phase during sintering, promoted the densification of ceramic, and reduced the sintering temperature of Mg4Nb2O9 ceramic. For the specimens sintered at 900 ℃, the average grain size was 0.75 m,εr was 19.7 and Q × fwas 5539 GHz. The grain size, density, εr and Q × f proportional increased with sintering temperature. Submicron Mg4Nb2O9 ceramic with microwave dielectric properties of εr = 13.07, Q ×f= 10858 GHz was obtained at 950 ℃. The well microwave dielectric properties of Mg4Nb2O9 ceramic made it an appropriate candidate for application on the low-temperature sintered microwave dielectric material.