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采用高温等静压（HIP）工艺，制备了纳米结构的单相SiC及Si3N4／SiC复相陶瓷，并通过X射线衍射分析、透射及高分辨电镜对其相组成及结构进行了表征．实验表明，在温度1850℃、压力200MPa条件下保温lh，可获得晶粒尺寸＜100nm、结构均匀、致密的单相SiC纳米结构陶瓷．对于St3N4／SiC复相体系，初始粉末的结晶形态对烧结体的结构有很大的影响.将初始粉末进行预处理后：在温度1750℃、压力150MPa条件下保温1h，可获得晶粒尺寸在50nm左右、结构致密、均匀的复相Si3N4／SiC纳米陶瓷材料．
Single phase SiC and Si3N4 / SiC multiphase nanostructured ceramics were prepared by high temperature isostatic pressing (HIP). Their phase compositions and structures were characterized by X-ray diffraction, transmission and high resolution electron microscopy. Experiments show that at a temperature of 1850 ℃, pressure 200MPa conditions lh, the crystal size can be obtained <100nm, uniform structure, dense single-phase SiC nano-structured ceramics. For the St3N4 / SiC composite phase, the morphology of the initial powder has a great influence on the structure of the sintered body.After pretreatment of the initial powder, the grain size of the sintered compact was kept at 1750 ℃ and 150MPa for 1h, 50nm or so, the structure of dense, uniform composite phase Si3N4 / SiC nano-ceramic materials.