亚微米氮化铝粉体改性微米氮化铝陶瓷的研究

Influence of Micro-AlN Ceramics Modified with Submicron Powders

以低温燃烧工艺结合碳热还原法制备获得的粒径30．180nm氮化铝粉体作为添加剂，探讨了不同量和不同粒径亚微米氮化铝粉体对微米氮化铝陶瓷烧结性能和热传导性能的影响规律。结果发现，在微米氮化铝粉体中添加适量的亚微米氮化铝粉体，可在一定程度上促进氮化铝陶瓷的烧结，在18000C即能实现致密化，并提高氮化铝陶瓷的热导率；亚微米氮化铝粉体的添加量以1．5wt％、粒径以120。150nm为最佳。但亚微米氮化铝粉体对微米氮化铝陶瓷的改性作用有限，18000C烧结得到陶瓷的极限密度仅为3．12g·cm2，低于氮化铝陶瓷的理论密度3．26g·cn-3，且陶瓷内部存在少量的气孔，其热导率为54．87W／（m·K）。

With 30-60 nm, 80-120 nm, 120-150 nm and 150-180 nm submicron AIN powders as additives, the influences of different contents and different sizes of the submicron powders on the sintering behavior and thermal conductivity of micro AIN ceramics were investigated. The results indicated that a proper addition of submicron powders to the micro-sized AIN powders could promote the sintering process and lower the sintering temperature to 1800℃, and the optimal addition was 1.5 wt% and the optimal size of submicron powders was 120-150 nm. With 1.5 wt% submicron powders in the size of 120- 150 rim, the AIN ceramics showed better sintering behavior, and the bulk density and thermal conductivity were 3.12 g.cm-1and 64.87 W/（m. K）, respectively.