PVB对梯度通孔结构SiC陶瓷显微结构和性能的影响  

Effect of PVB on Microstructure and Properties of SiC Ceramics with Gradient Pore Channel Structure

作　　者：王少锋[1,2] 汪长安[2] 孙加林[1] 黄勇[2] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]清华大学材料科学与工程系新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《机械工程材料》2011年第12期6-9,14,共5页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(90816019);国家"863"科技支撑计划重点项目(2007AA03Z435);国家"973"科技支撑计划重点项目(2006CB605207-2)

摘　　要：将叔丁醇(TBA)、聚乙烯醇缩丁醛(PVB)和SiC粉及烧结助剂配制成陶瓷浆料,通过定向冷冻和低温真空干燥的方法制备了具有梯度通孔结构的SiC陶瓷;研究了PVB含量对梯度通孔结构SiC陶瓷孔隙率、显微结构和力学性能的影响。结果表明:随PVB含量的增加,梯度通孔结构SiC陶瓷的孔径逐渐变小,抗压缩强度明显增大,开孔率变化不大;含PVB体积分数为3%的SiC陶瓷坯体,通过1 400℃的烧结,其开孔率为62.4%,轴向抗压强度可达87.5MPa。SiC ceramics with gradient pore channel structure were fabricated by directional freeze-casting and low temperature vacuum drying method. A slurry was selected, which consisted of tert-butyl alcohol （TBA）, polyvinyl butyral（PVB）, SiC powders and sintering additives. Effect of PVB content on porosity, microstrueture and mechanical properties of the SiC ceramics with gradient pore channel structure was studied. The results show that pore size gradually decreased and compressive strength of the SiC ceramics increased with the increase of PVB content, but open porosity had little change. The SiC ceramics containing avol% PVB sintered at 1 400℃ had an axial compressive strength of 87.5 MPa and a porosity of 62.4%.

关 键 词：SIC陶瓷 梯度通孔 定向冷冻 聚乙烯醇缩丁醛 

分 类 号：TQ174.75[化学工程—陶瓷工业]