含烧结助剂氮化硅陶瓷粉体的先驱体法制备及其烧结  

Preparation and Sintering of Silicon Nitride Ceramic Powders with Sintering Additives via Precursor Method

作　　者：李天昊 张健宁 何流 宋育杰[1,2,3] LI Tianhao;ZHANG Jianning;HE Liu;SONG Yujie(Qianwan Institute of CNITECH,Ningbo 315336,Zhejiang,China;Engineering Laboratory of Advanced Energy Materials,Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciences,Ningbo 315201,Zhejiang,China;Advanced Energy Science and Technology Guangdong Laboratory,Huizhou 516029,Guangdong,China)

机构地区：[1]宁波杭州湾新材料研究院,浙江宁波315336 [2]中国科学院宁波材料技术与工程研究所,浙江宁波315201 [3]先进能源科学与技术广东省实验室,广东惠州516029

出　　处：《硅酸盐学报》2024年第9期2767-2772,共6页Journal of The Chinese Ceramic Society

基　　金：国家重点研发计划(2021YFB3200500);宁波3315计划(2018A-03-A);先进能源科学与技术广东省实验室(HND20TDTHGC00)。

摘　　要：将金属钇和镁接枝三甲基硅基取代聚硅氮烷先驱体中,先驱体在热解过程中就可以原位生成金属氮化物烧结助剂,烧结助剂含量可通过钇、镁的接枝量进行精准调控。热解陶瓷为高纯氮化硅陶瓷,碳元素含量低于0.1%(质量分数),氧元素含量低于1.6%。含烧结助剂的氮化硅陶瓷可直接低温烧结制备高纯多孔氮化硅陶瓷块体,相对密度可达到99.4%,具有良好的硬度和导热性能。原位生成烧结助剂避免了额外添加烧结助剂造成的杂质引入和混合不均匀的问题,在高纯陶瓷烧结领域具有独特的优势。Introduction Uniform distribution in molecular level of ceramics could be achieved by polymer-derived method.Comparing to other methods,fewer crystal seeds existed in microstructure of polymer-derived ceramics,which made it more difficult to sinter.Up to now,few reports focused on the direct sintering of the polymer-derived ceramics.For silicon nitride sintering,the introduction of metal oxide additives caused defects in the lattice of silicon nitride because of oxygen atoms,which could affect the properties of the material.This work focused on the sintering behavior of polymer-derived ceramics and the issue of performance degradation caused by introducing oxygen elements in sintering additives.The metal elements were connected to the precursor molecule and formed the metal nitride sintering additives during pyrolysis process.The method could help to achieve the in-situ non-oxygen addition and uniformly mixing of sintering additives,and the followed low-temperature sintering could achieve the high-purity silicon nitride ceramics.Methods 4 mL of propylamine was added into a solution of trimethylsilyl chlorosilane monomer(14 g),yttrium chloride(0.14 g)and magnesium chloride(0.085 g)in pyridine(20 mL)at room temperature in N_(2) atmosphere.The mixture was warmed up to 120℃and stirred for 2 d.The mixture was then heated to 400℃for 4 h in N_(2) atmosphere and further heated to 1000℃with the rate of 10℃/min,finally the mixture were holding at 1000℃for 4 h and then cooled to room temperature naturally.A white silicon nitride powder SiN-1 was obtained.Silicon nitride powders SiN-2 and SiN-3 were prepared by the same method,in which 0.055 g magnesium chloride was added in SiN-2 and no magnesium chloride was added in sample SiN-3.Silicon nitride ceramics was prepared through spark plasma sintering of silicon nitride powders in 1450℃,45 MPa for 30 min.Before characterization of the silicon nitride ceramics,surface of it was pre-polished.Results and discussion Based on trimethylsilyl-substituted polysilazane prec

关 键 词：氮化硅 先驱体 烧结助剂 原位 多孔陶瓷 

分 类 号：TQ12[化学工程—无机化工]