微硅粉对堇青石质轻集料烧胀性能的影响  

Effect of Silica Fume on the Sintering Expansion Behavior of Cordierite Lightweight Aggregate

作　　者：马鑫 张礼华[1] 刘来宝[1] 刘川北[1] 张红平[1] 荆桂花 MA Xin;ZHANG Lihua;LIU Laibao;LIU Chuanbei;ZHANG Hongping;JIN Guihua(School of Materials Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Shandong Luyang Share Company Limited,Zibo 256100,Shandong,China)

机构地区：[1]西南科技大学材料科学与工程学院,四川绵阳621010 [2]山东鲁阳股份有限公司,山东淄博256100

出　　处：《西南科技大学学报》2020年第4期24-29,共6页Journal of Southwest University of Science and Technology

基　　金：国家重点研发计划(2019YFC1904900);国家自然科学基金青年基金(51808464);国家自然科学基金面上项目(51978590)。

摘　　要：以粉煤灰、铝矾土、轻烧镁砂和微硅粉(石英粉)为原料(其质量分数分别为38.2%,32.0%,10.8%,19.0%),于1230℃下制备出了堇青石质轻集料。通过XRD,SEM,数字图像处理和物理性能测试等手段研究了非晶质微硅粉取代晶质石英粉对轻集料烧胀性能的影响。结果表明:在不改变原料化学组成和烧成制度前提下,微硅粉取代晶质石英粉能促进堇青石晶体生长发育和轻集料的烧胀;随着微硅粉取代率增加,轻集料吸水率增加,体积密度和抗压强度下降,当取代率低于50%时,轻集料堆积密度580 kg/m^3,1 h吸水率4.54%,抗压强度5.55 MPa,满足高性能轻集料要求。In this study,the cordierite-based lightweight aggregate was prepared by using 38.2%fly ash,32.0%bauxite,10.8%light burned magnesia and 19.0%(silica fume/quartz powder)at the temperature of 1230℃.Besides,by means of XRD,SEM,digital image processing and physical performance testing,the effect of quartz powder substituted by silica fume on the sintering expansion behavior of lightweight aggregate was studied.The results show that the silica fume is beneficial to the growth of cordierite and promotes the sintering expansion behavior of lightweight aggregates without significant changes in the chemical composition of raw materials and sintering temperature.With the increase of silica fume substitution,the water absorption of lightweight aggregate increases while the volume density and the compressive strength decrease.When the substitution rate is lower than 50%,the bulk density of lightweight aggregates is smaller than 580 kg/m 3,the water absorption rate for 1 h is less than 4.54%and the compressive strength is greater than 5.55 MPa,which can meet the requirements of high-performance lightweight aggregate.

关 键 词：微硅粉 堇青石 轻集料 烧胀性能 

分 类 号：TU528[建筑科学—建筑技术科学]