中文摘要：

放电等离子体烧结(SPS)技术作为一种比较新的烧结技术已经被广泛用于制备各种材料。本文以3Y.ZrO2粉体和石墨烯纳米片为原料，采用SPS技术制备了石墨烯纳米片复合ZrO2陶瓷，利用扫描电镜、透射电镜和X射线衍射仪等对烧结样品的显微结构和晶相进行了表征，同时对所制备材料的密度、显微硬度和断裂韧性进行了测试。结果表明，烧结温度和石墨烯纳米片对所制备样品的显微结构和性能都有显著的影响。随着烧结温度的增加，样品的密度提高，晶粒生长明显。而石墨烯纳米片的引入则显著抑制了ZrO2晶粒的生长，但是由于分散性问题，其显微硬度和断裂韧性反而略有降低。

英文摘要：

As a novel sintering technology,spark plasma sintering(SPS)has been widely used to prepare various materials.In this work,graphene nano-sheet/ZrO2composite ceramics was fabricated via SPS by using nano-sized ZrO2-3Y powders and graphene nano-sheet as raw materials.The phase composition and morphology of the as-sintered samples were characterized by using scanning electron microscope,transmission electron microscope,X-ray diffraction(XRD),etc.The porosity,Vickers hardness and fracture toughness of the as-sintered samples were also measured.The results showed that the sintering temperature and incorporation of graphene nano-sheet have significant impacts on the microstructure and mechanical properties of the as-sintered samples.With the increase of the sintering temperature,the density of the ZrO2samples increased,and the grain sizes grew obviously.The incorporation of graphene nano-sheet restricted the growth of ZrO2grain dramatically.However,the Vickers hardness and fracture toughness of as-sintered samples decreased slightly due to the bad dispersion of the graphene nano-sheet in ZrO2matrix.