碳掺杂对碳化硅膜支撑体结构与性能的影响  

Effect of pore-forming agent carbon powder on properties of SiC membrane supports

作　　者：李冬燕 韩峰 王建鑫 徐鹏 仲兆祥[3] LI Dongyan;HAN Feng;WANG Jianxin;XU Peng;ZHONG Zhaoxiang(Nanjing Polytechnic Institute,Nanjing 210048,China;Nanjing Industrial Technology Research Institute of Membrane Material Co.,Ltd.,Nanjing 211800,China;Nanjing Tech University,Nanjing 210009,China)

机构地区：[1]南京科技职业学院化工与材料学院,南京210048 [2]南京膜材料产业技术研究院有限公司,南京211100 [3]南京工业大学,南京211816

出　　处：《膜科学与技术》2019年第5期65-72,共8页Membrane Science and Technology

基　　金：江苏高校“青蓝工程”资助;国家重点研发计划专项(2016YFC0204000);江苏省基础研究计划(自然科学)(BK20180164)

摘　　要：以200μm碳化硅为骨料,氧化锆为烧助剂,莫来石纤维为增强剂,碳粉为造孔剂,经过混合造粒后干压成型制得生坯,然后通过高温原位反应烧结获得大孔径、高孔隙率的SiC膜支撑体.本文主要考察了造孔剂碳粉粒径和含量对SiC膜支撑体性能的影响,并测试膜支撑体的高温抗热震性能和高温热膨胀特性.研究结果显示,当碳粉粒径和质量分数分别为20μm和15%,烧结温度1 450℃,保温时间为4 h时,制备的碳化硅支撑体有较好的综合性能,支撑体抗折强度达24 MPa,开口孔隙率为42.5%,平均孔径50.5μm,1 kPa压力下气体流量达到1400 m^3/(m^2 h).SiC膜支撑体热膨胀系数为5.0×10^-6 K^-1,并在30~800℃下连续冷热循环60次以上,仍然保持较高的抗折强度,是较好的高温气体过滤材料.The porous SiC ceramic supports were prepared by dry press forming method.The mixed powder contained 200μm SiC particles,sintering aids ZrO 2,reinforcement material mullite fibers and pore forming agent carbon powder.The particle size and content of carbon powder were studied on porosity,bending strength,microstructure,average pore size and gas flux.At the same time,the thermal shock resistance and thermal expansion properties were also investigated in the experiments.The results showed that when the particle size and content of the carbon powder were 20μm and 15%,respectively,the prepared silicon carbide supports had better comprehensive performances.The bending strength,porosity and average pore diameter of SiC supports were 24 MPa,42.5%,and 50.5μm,respectively.The silicon carbide supports still maintained a high mechanical strength after cycled 60 times at 30~800℃.In addition,it was found that the temperature resistance of the SiC supports could reach 1275℃and the coefficient of thermal expansion maintained at 5.0×10^-6 K^-1.The above results demonstrate this material possesses a good application prospects in high gas purification.

关 键 词：碳化硅 造孔剂 多孔陶瓷 抗热震性 

分 类 号：TQ174.6[化学工程—陶瓷工业]