亚稳态纳米晶氧化锆片状粉体的制备及冷烧结  

Preparation and Cold Sintering Properties of Metastable Nanocrystalline Zirconia Flake Powders

作　　者：张贺新 丁奇 范宇驰[2] 江莞[2] ZHANG Hexin;DING Qi;FAN Yuchi;JIANG Wan(School of Materials Science and Engineering,Donghua University,Shanghai 201620,China;Functional Materials Research Center,Donghua University,Shanghai 201620,China)

机构地区：[1]东华大学材料科学与工程学院,上海201620 [2]东华大学功能材料研究中心,上海201620

出　　处：《硅酸盐学报》2023年第7期1819-1826,共8页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(52122203)。

摘　　要：冷烧结技术自引入以来已有多种陶瓷材料获得了成功制备,但作为重要结构陶瓷的氧化锆其冷烧结致密度仍然偏低。为了提高冷烧结氧化锆陶瓷的致密度,采用亚稳态的纳米晶氧化锆片状粉体进行了研究。首先利用氧化石墨烯为模板,以三(羟甲基)氨基甲烷为沉淀剂制备了含56%四方相的片状氧化锆。然后,从烧结助剂、温度、压力、液相掺量4个因素出发探索了对氧化锆致密度以及微观结构的影响。结果表明:在HCl作为烧结助剂、300℃、500 MPa、液相掺量为20%(质量分数)的冷烧结工艺条件下,实现了约70%的致密度,远高于目前冷烧结氧化锆致密度的报道值。致密度的提升主要得益于烧结中亚稳态氧化锆的相变以及助剂对片状粉体的颗粒重排和溶解-沉淀作用。此外,孔隙率的降低使得冷烧结氧化锆陶瓷的杨氏模量和抗弯强度分别达到了24 GPa和20 MPa。Although some ceramic materials are prepared via cold sintering,the relative density of zirconia as an important structural ceramic is still low.To improve the relative density of cold sintered zirconia ceramics,metastable nanocrystal zirconia flakes were used as a starting powder.ZrO2 sheet containing 56%tetragonal phase was prepared with graphene oxide as a template and trihydroxymethyl aminomethane as a precipitator.The influence of sintering additives,temperature,pressure and liquid content on the relative density and microstructure of ZrO2 was investigated.The results show that the relative density of approximately 70%is achieved under the condition of cold sintering with HCl as a sintering additive,300℃,500 MPa and liquid content of 20%(in mass fraction),which is much higher than the previously reported relative density of cold sintered zirconia.The increase of relative density is mainly due to the phase transformation of the sintered metastable ZrO2 and the particle rearrangement and solution-precipitation of the flake powder.The Young modulus and flexural strength of cold-sintered ZrO2 ceramics are 24 GPa and 20 MPa,respectively,due to the decrease of porosity.

关 键 词：氧化锆陶瓷 冷烧结 致密度 烧结助剂 相变 

分 类 号：TQ174.1[化学工程—陶瓷工业]