水热法合成陶瓷LaPO_4的微波介电性能（英文）

Microwave Dielectric Properties of LaPO_4 Ceramics Synthesized by a Hydrothermal Method

摘要：通过水热法和固相反应法制备了LaPO4粉体，分别在1030～1340℃和1300～1460℃范围内对粉体进行了烧结，得到了LaPO4陶瓷，研究对比了两种方法得到的陶瓷的烧结行为和微波介电性能。结果表明：和固相法相比，水热法得到的陶瓷由于粉体粒径小更易于烧结，微波介电性能更优；在1260℃条件下烧结2h得到的水热法陶瓷具有最好的微波介电性能：介电常数为10．2，Q×f值为29704GHz（f=10．2GHz），谐振频率温度系数值为-58．6ppm/℃；水热法陶瓷的Q×f值为固相法的2．47倍，烧结温度比固相法低140℃。

Lanthanum orthophosphate （LaPO4） ceramics were obtained by using hydrothermal prepared powders and solid-state reaction prepared powders in a sintering temperature range of 1030-1340℃ and 1300-1460℃, respectively The sintering and microwave dielectric properties of hydrothermal processed LaPO4 ceramics were compared with those of solid-state reaction processed LaPO4. The results showed that hydrothermal processed LaPO4 had a higher sinterability and better microwave dielectric properties due to its much finer particle size when compared with solid-state reaction processed LaPO4. The best microwave dielectric properties of the hydrothermal processed LaPO4 ceramics were obtained when the ceramics sintered at 1260℃ for 2 h with a permittivity-10.2, a Q×f value about 129704 GHz （at 10.2 GHz） and a temperature coefficient value of-58.6×10^-6/℃. The Q×f value of hydrothermal processed LaPO4 ceramics was 2.47 times greater than that of solid-state reaction processed LaPO4 ceramics, while the sintering temperature of the former was 140℃ lower than that of the latter in the literature.