水基凝胶注模制备高导热氮化硅陶瓷  

Preparation of High Thermal Conductivity Silicon Nitride Ceramic by Aqueous Gel-Casting

作　　者：田云龙 祁海[1] 张培志[1] 郭方全[1] 韩伟月 TIAN Yunlong;QI Hai;ZHANG Peizhi;GUO Fangquan;HAN Weiyue(Shanghai Key Laboratory of Engineering Materials Application and Evaluation,Shanghai Research Institute of Materials,Shanghai 200437,China)

机构地区：[1]上海材料研究所,上海市工程材料应用与评价重点实验室,上海200437

出　　处：《硅酸盐学报》2022年第9期2351-2357,共7页Journal of The Chinese Ceramic Society

基　　金：上海材料研究所创新项目。

摘　　要：获得低黏度的氮化硅陶瓷浆料,并利用水基凝胶注模成型工艺制备高导热氮化硅陶瓷。探究和讨论了MgO对氮化硅陶瓷的浆料流变性及热导率的影响。结果表明:MgO在浆料中造成颗粒团聚导致黏度上升,并随着MgO添加量的提高,浆料黏度对pH值越来越敏感;合理调节pH值和分散剂的添加量能获得低黏度的陶瓷浆料;利用水基凝胶注模成型工艺制备了热导率为83.7 W·m^(-1)·K^(-1),抗弯强度为945 MPa,断裂韧性为8.4 MPa·m^(1/2)的氮化硅陶瓷,表明环保的水基成型工艺制备高导热氮化硅陶瓷是可行的。High thermal conductivity silicon nitride ceramics were prepared via aqueous gel-casting with a slurry of a low viscosity.The effect of MgO sintering aid on the rheological properties of slurry and the thermal conductivity of silicon ceramics was investigated.The results show that MgO sintering aid causes the particles aggregation and increases the slurry viscosity.The slurry viscosity becomes sensitive to the pH value change when the addition amount of MgO increases.A ceramic slurry with a low viscosity is achieved by adjusting p H value and dispersant concentration.The thermal conductivity,bending strength,and fracture toughness of the sample prepared by aqueous gel-casting can reach 83.7 W·m^(-1)·K^(-1),945 MPa,and 8.4 MPa·m^(1/2),respectively.The feasibility of high thermal conductivity silicon nitride ceramics prepared by aqueous gel-casting was verified.

关 键 词：氮化硅 水基凝胶注模成型工艺 黏度 氧化镁 热导率 

分 类 号：TG174.75[金属学及工艺—金属表面处理]