ρ-Al_(2)O_(3)复合铝酸钙水泥烧结助剂对多孔碳化硅陶瓷性能的影响  

Effect ofρ-Al_(2)O_(3)-CAC composite sintering aid on properties of porous SiC ceramics

作　　者：潘进文 姜洪义[1] Pan Jinwen;Jiang Hongyi(Ecological Environment Laboratory,Wuhan University of Technology,Wuhan 430070,Hubei,China;不详)

机构地区：[1]武汉理工大学生态环境材料实验室,湖北武汉430070

出　　处：《耐火材料》2024年第5期376-380,386,共6页Refractories

摘　　要：为了提高多孔碳化硅陶瓷的性能,以绿碳化硅为主原料,石墨为造孔剂,用铝酸钙水泥(CAC)和水合氧化铝(ρ-Al_(2)O_(3))配制成复合烧结助剂(ρ-Al_(2)O_(3)-CAC),经1450℃保温3 h,制备多孔碳化硅陶瓷。研究了ρ-Al_(2)O_(3)-CAC加入量(加入质量分数为2.5%~20%)对多孔碳化硅陶瓷物相组成、显微结构和性能的影响。结果表明:1)ρ-Al_(2)O_(3)-CAC能促进碳化硅的氧化,并与碳化硅氧化生成的SiO_(2)发生原位反应,形成玻璃-莫来石复相结合,同时还在结合相中引入气泡,气泡会随ρ-Al_(2)O_(3)-CAC加入量的增加而长大;2)当ρ-Al_(2)O_(3)-CAC的加入量为12.5%(w)时,制得的多孔碳化硅陶瓷综合性能最佳,其显气孔率为39.1%,室温弯曲强度为39.3 MPa,透气度为26.74 m^(3)·h^(-1)·kPa^(-1)·m^(-2),抗热震性最优。In order to improve the performance of porous SiC ceramics,green silicon carbide was used as the main raw material,graphite as the pore forming agent,andρ-Al_(2)O_(3)-CAC as a composite sintering aid which is prepared from calcium aluminate cement(CAC)and hydrated alumina(ρ-Al_(2)O_(3)),firing at 1450℃for 3 h.The effect of theρ-Al_(2)O_(3)-CAC addition(2.5%-20%,by mass)on the phase composition,microstructure,and properties of porous SiC ceramics was studied.The results reveal several key findings:ρ-Al_(2)O_(3)-CAC facilitates the oxidation of silicon carbide and reacts in situ with SiO_(2) produced by the oxidation of silicon carbide,forming a glass-mullite composite;bubbles are introduced into the composite phase,with their size increasing with the risingρ-Al_(2)O_(3)-CAC addition;at anρ-Al_(2)O_(3)-CAC addition of 12.5%,the prepared porous SiC ceramics exhibit the optimal comprehensive properties:the apparent porosity is 39.1%;the flexural strength is 39.3 MPa;the air permeability reaches 26.74 m^(3)·h^(-1)·kPa^(-1)·m^(-2),and the thermal shock resistance is the best.

关 键 词：多孔碳化硅陶瓷 ρ-Al_(2)O_(3)-CAC 玻璃-莫来石复相结合 抗热震性 透气度 

分 类 号：TQ174.75[化学工程—陶瓷工业]