热处理对共沉淀法制备YAG纳米粉体性能的影响

Influence of Heat Treatment on the Properties of YAG Nano-sized Powder by Co-precipitation Method

以Al（NO3）3和Y（NO3）3为原料，采用共沉淀法制备出粒度大小为60-100nm，颗粒呈球形的纯相YAG纳米粉。研究了前驱物在不同条件下热处理对YAG纳米粉体性能的影响，并对前驱物在焙烧过程中的物相变化进行了观察。发现延长前驱物在低温下的干燥时间会导致晶粒尺寸增大，而采用在晶化温度前后分别进行保温的方法可在较低的温度获得纯相的YAG粉体。对比了焙烧温度和保温时间对产物粒度的影响，结果表明：在保证粉体晶化完全的前提下，升高焙烧温度比延长保温时间对晶粒尺寸有更显著的影响。

Pure phase yttrium aluminum garnet （YAG） nanopowders were synthesized with aluminum nitrate and yttrium nitrate as the raw materials by the co-precipitation method. The primary particles are spherical and measured to be 60-100nm in diameter. The influence of different heat-treatment conditions on the properties of YAG nano-sized powders was studied, and phase transformations were observed during the calcination process of precursor. It was found that the grain size increased when the drying time for the precursor was prolonged at low temperature. Furthermore, the pure-phase YAG powder was obtained at low temperature by two-step ,~intering at temperatures below and above the crystallization temperature respectively. The influence of calcination temperature and calcination time on the nanopowder size was compared. Results show that a high calcination temperature is more beneficial than the long calcination time to increase the particle size under the condition of making powders crystallization completely.