采用聚硅氧烷SR355与纳米Ni粉混合物连接无压烧结SiC陶瓷  

Joining of pressureless sintered SiC using polysiloxane SR355 with active additive Ni nanopowder

作　　者：李树杰[1] 刘文慧[1] 卢越焜[1] 李星国[2] 毛样武[1] 

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100191 [2]北京大学化学与分子工程学院,北京100871

出　　处：《复合材料学报》2008年第6期72-76,共5页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(50271003)

摘　　要：无压烧结SiC陶瓷(SSiC)是重要的高温结构材料,连接技术是扩大其应用范围的关键技术之一。将活性填料纳米Ni粉添加到聚硅氧烷SR355中制成连接材料,通过反应成形连接工艺连接SSiC。研究了纳米Ni粉对SR355的裂解过程和陶瓷产率的影响,同时也研究了填料含量和连接温度对连接件强度的影响。结果表明,纳米Ni粉的加入促进了SR355的裂解并提高了其陶瓷产率。当纳米Ni粉含量为1%(质量分数)、连接温度为1050℃时,连接件经3次浸渍增强处理后的连接强度达到最大值。微观结构研究表明,连接层均匀致密,且与母材间界面结合良好,界面处发生了元素的扩散,纳米Ni粉在连接过程中参与了化学反应并促进了界面结合。Pressureless sintered SiC （SSiC） is an important high temperature structure material, and the joining technique is one of the key techniques to extend its application. Joining of SSiC was carried out by the reaction joining process using polysiloxane （SR355） with active additive Ni nanopowder as joining materials. The pyrolysis of SR355 with Ni nanopowder was studied. The effects of the content of active additive and joining temperature on the joining strength of joints were investigated. The results show that the active additive promotes the pyrolysis of SR355. The maximum joining strength of the joints is obtained at the joining temperature of 1050~C with the Ni nanopowder mass fraction of 1~ and three times of the reinforcement treatments. The microstructure and composition of the interracial area were analyzed by SEM and EDX. The results indicate that the interlayer is densified. The micrographs show good contact at the interfaces. The diffusion of elements takes place at the interfaces. The active additive Ni nanopowder participates in the chemical reactions in the joining process, which contributes to the interfacial bonding, resulting in the increasing of joining strength of the joints.

关 键 词：陶瓷连接 聚硅氧烷 碳化硅 纳米Ni粉 

分 类 号：TB332[一般工业技术—材料科学与工程]