熔渗反应烧结泡沫SiC的组织及性能  

Microstructure and properties of silicon carbide foam by infiltration sintering process

作　　者：田冲[1] 曹小明[1] 杨振明[1] 杨永进[1] 张劲松[1] TIAN Chong;CAO Xiaoming;YANG Zhenming;YANG Yongjin;ZHANG Jinsong(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China)

机构地区：[1]中国科学院金属研究所,沈阳110016

出　　处：《功能材料》2018年第3期3182-3186,3191,共6页Journal of Functional Materials

基　　金：国家重点研发计划资助项目(2017YFB0603400);国家高技术研究发展计划(863计划)资助项目(2015AA03A602)

摘　　要：采用有机泡沫浸渍结合熔渗反应烧结技术制备了一种高性能泡沫SiC,该种泡沫陶瓷由SiC陶瓷孔筋形成类似于泡沫的三维网络连通结构,平均孔径尺寸约2 mm,相对密度15%~42%(体积分数),具有高的可控性,其强度随密度增加而提高,压缩强度11~48 MPa,弯曲强度7~25 MPa。研究了材料受力时的变形行为,结果表明,该种泡沫SiC具有不同于常见报道中的泡沫陶瓷的形变机制,其应力应变曲线只有弹性变形阶段,原因在于材料整体均匀性高,陶瓷孔筋组织致密且晶粒细小,受力时表现出良好的整体协调性。材料具有优良的热导性能。同时该种材料还可以加工成复杂形状,可适应各种应用需求。Open-cell silicon carbide(SiC)foams with high performance were prepared from aqueous slurry by the organic foam impregnation and infiltration reaction sintering process with polyurethane sponges as the substrates.SiC ceramic struts formed a three-dimensional network connected structure similar to foam.The cells in the foams are randomly oriented,and mostly homogeneous in size and shape.Average pore size is about2mm.Controllable relative densities varied fromabout15vol%to about42vol%,which leaded to compressive strengths of SiC foams ranged betweenabout11MPa to about50MPa and flexural strengths varied from about7MPa to about25MPa.Deformation behavior of the SiC foams was investigated.When SiC foams were deformed,the stress-strain curve showed approximately only one linear-elastic region and this was different from those of ceramic foams reported.This is possible because of the struts with fine microstructure had high density and high strength.Therefore,the SiC foams are uniform and the struts could response homogeneously to load transmitted through the foams.The thermal conductivity measurement indicated that the materials had excellent thermal conductivity properties and the materials could be processed into a complex shape that could be adapted to a variety of application requirements.

关 键 词：泡沫SiC 相对密度 强度 线弹性 导热系数 

分 类 号：TQ174.7[化学工程—陶瓷工业]