采用发泡-流延成型工艺制备多孔莫来石发泡陶瓷  

Preparation of porous mullite foamed ceramics by foaming-tape casting

作　　者：徐娜 王挺 Xu Na;Wang Ting(Inner Mongolia Technical College of Construction,Hohhot 010070,Inner Mongolia Autonomous Region,China;不详)

机构地区：[1]内蒙古建筑职业技术学院,内蒙古呼和浩特010070 [2]哈尔滨工业大学,黑龙江哈尔滨150001

出　　处：《耐火材料》2020年第4期330-333,共4页Refractories

基　　金：深圳知识创新计划基金(JCYJ20150402103811551)。

摘　　要：以氧化铝微粉为原料,聚丙烯酰胺为分散剂,脂肪醇聚氧乙烯醚硫酸钠(AES)为发泡剂,氯化铵为固化剂,硅溶胶为硅源和结合剂,采用发泡-流延成型工艺制备多孔莫来石发泡陶瓷。探究了脂肪醇聚氧乙烯醚硫酸钠(AES)发泡剂的添加量(质量分数分别为0.5%、1%、2.5%、3%、3.5%和5%)和烧结温度(1450、1500、1550、1600和1700℃)对发泡陶瓷的体积密度、耐压强度、显气孔率以及显微形貌的影响。结果表明:随着发泡剂AES添加量的增加,试样的体积密度和耐压强度先降低后增加,显气孔率先升高后降低。当发泡剂加入量为3%(w)时,烧结温度为1450℃时,莫来石相基本未形成。随着烧结温度升高,刚玉和方石英原位反应生成莫来石。发泡剂AES的添加量3%(w)、烧结温度1550℃为发泡陶瓷最优的制备条件。此时,体积密度为0.25 g·cm-3,耐压强度为4.7 MPa,显气孔率为56.4%,800℃下的热导率为0.095 W·m-1·K-1,满足T/CECS 480—2017《发泡陶瓷保温板应用技术规程》中规定的发泡陶瓷保温隔热板Ⅳ型主要性能指标。Porous mullite foamed ceramics were prepared by the foaming-tape casting process with alumina micropowder as the starting material,polyacrylamide as the dispersant,and sodium fatty alcohol polyoxyethylene ether sulfate(AES)as the foaming agent,ammonia chloride as the curing agent,and silica sol as the Si source and the binder.The effects of the AES additions(0.5%,1%,2.5%,3%,3.5%,and 5%,by mass)and the sintering temperatures(1450,1500,1550,1600,and 1700℃)on the bulk density,the compressive strength,the porosity and the microstructure of foamed ceramics were investigated.The results show that with the AES addition increasing,the bulk density and the compressive strength of the samples decrease first and then increase,while the apparent porosity increases first and then decreases;when adding 3%of AES and sintering at 1450℃,the mullite is not formed;with the sintering temperature increasing,corundum and cristobalite in situ react to form mullite;the optimum conditions for the preparation of the foamed ceramics are adding 3%of AES and sintering at 1550℃,and the foamed ceramics have the bulk density of 0.25 g·cm-3,the compressive strength of 4.7 MPa,the apparent porosity of 56.4%and the thermal conductivity of 0.095 W·m-1·K-1 at 800℃,which meet the main performance index of typeⅣfoamed ceramic thermal insulation panel in the standard of T/CECS 480—2017 Technical specification for application of foamed ceramic thermal insulation panels.

关 键 词：发泡法 溶胶-凝胶 脂肪醇聚氧乙烯醚硫酸钠 莫来石 发泡陶瓷 

分 类 号：TQ174.76[化学工程—陶瓷工业]