摘要
为降低多孔碳化硅陶瓷的烧结温度,降低生产成本,使用210 μm的近等径碳化硅颗粒为骨料,以木炭粉为造孔剂,采用以铝溶胶和硅溶胶按1∶ 5质量比配成的混合溶胶以及 d 50 =12.4 μm的ρ-Al2O3粉为结合剂,于1 400 ℃空气气氛下常压烧结2 h制备出氧化物结合多孔碳化硅试样。研究了试样的性能,并观察显微结构变化。结果表明:制备的氧化物结合多孔碳化硅O形环强度为23.4 MPa,抗热震试验10次后,强度降低到 19.7 MPa 。试样的平均孔径为64.3 μm,显气孔率为38.1%,在过滤风速1 m·min^-1 时,10 mm壁厚试样的阻力降为30.2 Pa;在1 200 ℃保温100 h热处理后阻力降增加到39.7 Pa。当温度超过1 000 ℃时,由于碳化硅表面氧化改变了孔隙结构,使得阻力降增加,因此不宜在超过1 000 ℃温度下长期使用。
In order to reduce the sintering temperature and production cost,porous silicon carbide ceramic specimens were prepared using silicon carbide particles (near equal diameter of 210 μm) as aggregates,charcoal powder as the pore-forming agent,and mixing sol (alumina sol∶ colloidal silica=1∶ 5,by mass) and ρ-Al2O3 powder ( d 50 =12.4 μm) as binders.Properties of specimens after sintering at 1 400 ℃ for 2 h in air were studied and the microstructure was observed.The results show that the O-ring strength of the as-made porous SiC is 23.4 MPa;the strength decreases to 19.7 MPa after 10 cycles of thermal shock;the specimen has average pore size of 64.3 μm and apparent porosity of 38.1%;the pressure drop of the specimen with thickness of 10 mm is 30.2 Pa under filtration velocity of 1 m·min^-1 ,but the pressure drop increases to 39.7 Pa after heat treatment at 1 200 ℃ for 100 h;when the temperature exceeds 1 000 ℃,the surface oxidation of SiC changes the pore structure of the material,which increases the pressure drop.Therefore,oxide bonded porous silicon carbide is ceramic not suitable for long-term application above 1 000 ℃.
作者
刘永启
叶根喜
孙广超
陈正宗
刘家栋
栗艳兵
刘开琪
Liu Yongqi;Ye Genxi;Sun Guangchao;Chen Zhengzong;Liu Jiadong;Li Yanbing;Liu Kaiqi(Nanjing Belan Environmental Technology Co.,Ltd.,Nanjing 211000,Jiangsu,China)
出处
《耐火材料》
CAS
北大核心
2019年第4期258-262,共5页
Refractories
基金
国家重点研发计划资助项目(2016YFB0601100)
关键词
氧化物结合
多孔碳化硅
阻力降
O形环强度
过滤速度
oxide bonded
porous silicon carbide
pressure drop
O-ring strength
filtration velocity
