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本文介绍用非均相沉淀法制备的纳米SiC－Al2O3复合粉体经放电等离子超快速烧结得到晶内型的纳米复相陶瓷，超快速烧结的升温速率为600℃／min，在烧结温度不保温，迅即在3min内冷却至600℃以下．与热压烧结相比，可降低烧结温度200℃以上．力学性能研究结果表明，在1450℃超快速烧结得到的纳米复相陶瓷的抗弯强度高达1000MPa，维氏硬度为19GPa，断裂韧性也比Al2O3有所提高．TEM像显示纳米SiC颗粒大多分布在Al2O3母体晶粒内，而断裂表面的SEM像表明，穿晶断裂是其主要的断裂模式，这是所制备的纳米复相陶瓷力学性能大幅提高的主要原因．
In this paper, the nano-SiC-Al2O3 composite powders prepared by heterogeneous precipitation method were obtained by ultra-rapid spark plasma sintering of sintered nanocomposite ceramics. The heating rate of ultra-rapid sintering was 600 ℃ / min. , Quickly cooled to below 600 ℃ in 3min. Compared with hot-press sintering, the sintering temperature can be lowered 200 ℃. Mechanical properties of the results show that the ultra-fast sintering at 1450 ℃ nanocomposite ceramic flexural strength up to 1000MPa, Vickers hardness of 19GPa, fracture toughness is also higher than that of Al2O3. TEM images show that the nano-SiC particles are mostly distributed in the matrix of Al2O3 matrix, while the SEM images of the fracture surface show that transgranular fracture is the main fracture mode, which is the main reason for the substantial improvement of the mechanical properties of the prepared nano-composite ceramics.