微波均相合成YAG纳米粉体及其可烧结性研究

采用微波辐照尿素法均相合成技术制备了具有良好分散性的纳米级单相YAG粉体,分析了YAG前驱体的化学组成及其物相变化过程,并对YAG粉体的粒度和形貌进行了表征,结果表明在尿素与钇铝离子的摩尔比为15:1的低尿素用量条件下,合成的无定形前驱物经900℃煅烧直接结晶生成YAG单相粉体,在反应体系中添加适量(NH₄)₂SO₄可使YAG粉体的粒度分布和可烧结性明显改善,添加8%的(NH₄)₂SO₄得到的YAG粉体具有良好的可烧结性,在1500℃烧结即可实现致密化.

Synthesis and Sinterability of YAG Nanopowders by Microwave Homogeneous Precipitation

The low-agglomerated single-phase YAG nanopowders were synthesized by the microwave homogeneous precipitation in the presence of urea. The composition and transformations during calcination of YAG precursor were analyzed by IR, DTA/TG and XRD. The size and morphology of YAG powders were characterized by LD and TEM. Results show that the amorphous precursor crystallizes directly to single-phase YAG powders upon calcining to 900℃ that was synthesized under urea]/metal ions] molar ratio of 15. The size distribution and sinterability of YAG powders are obviously improved by adding (NH₄)₂SO₄ into the reaction solution. YAG powders obtained from the precursor with the (NH₄)₂SO₄ content of 8% have good sinterability and can be highly densified at 1500℃.