Open-cell mullite ceramic foams derived from porous geopolymer precursors with tailored porosity  

作　　者：Jiahuan SHAO Chengying BAI Xinyu LI Kun YANG Ting ZHENG Yingjie QIAO Lili ZHANG Hongqiang LI Paolo COLOMBO 

机构地区：[1]Key Laboratory of Superlight Materials and Surface Technology,Ministry of Education,College of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China [2]College of Civil Engineering,Hunan University,Changsha 410082,China [3]Department of Industrial Engineering,University of Padova,via Marzolo,Padova 35131,Italy [4]Department of Materials Science and Engineering,The Pennsylvania State University,State College 16802,USA

出　　处：《Journal of Advanced Ceramics》2023年第2期279-295,共17页先进陶瓷（英文）

基　　金：supported by the National Natural Science Foundation of China (52002090);the Heilongjiang Postdoctoral Science Foundation Funded Project (LBHZ19051);the Fundamental Research Funds for the Central Universities (XK21000210);the Scientific Research Foundation for the Returned Overseas Chinese Scholars of Heilongjiang Province (2019QD0002);the open fund from Key Laboratory of Superlight Materials and Surface Technology,Ministry of Education (XK2100021044).

摘　　要：Porous geopolymer precursors were firstly prepared by the direct foaming method using bauxite,fly ash(FA),and metakaolin(MK)as raw materials,and porous mullite ceramics were prepared after ammonium ion exchange and then high-temperature sintering.The effects of chemical foaming agent concentration,ion-exchange time,and sintering temperature on porous geopolymerderived mullite ceramics were studied,and the optimal preparation parameters were found.Studies have shown that the concentration of blowing agent had great influence on open porosity(q)and porosity and cell size distributions of geopolymer samples,which in turn affected their compressive strength(σ).Duration of the ion exchange had no obvious effect on the sintered samples,and the amount of mullite phase increased with the increase in the sintering temperature.Mullite foams,possessing an open-celled porous structure,closely resembling that of the starting porous geopolymers produced by directly foaming,were obtained by firing at high temperatures.Stable mullite(3Al_(2)O_(3)·2SiO_(2))ceramic foams with total porosity(ε)of 83.52 vol%,high open porosity of 83.23 vol%,and compressive strength of 1.72 MPa were produced after sintering at 1400 for 2 h in℃ air without adding any sintering additives using commercial MK,bauxite,and FA as raw materials.

关 键 词：porous mullite ceramic POROSITY porous geopolymer precursor direct foaming nanophase strengthening 

分 类 号：TQ174.758.11[化学工程—陶瓷工业]