微粉对凝胶注模氧化铝耐火材料性能和结构的影响  

Effect of Micro-powder on Properties and Structure of Alumina Refractories with Gel-Casting Processing

作　　者：魏瀚[1,2] 闫昕 徐琳琳 徐如林 WEI Han;YAN Xin;XU Linlin;XU Rulin(Ruitai materials Technology Co.Ltd.,China Building materials Academy,Beijing 100024,China;School of material Science and Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China)

机构地区：[1]中国建筑材料科学研究总院瑞泰科技股份有限公司,北京100024 [2]郑州大学材料科学与工程学院,河南郑州450001

出　　处：《中国陶瓷工业》2021年第2期5-8,共4页China Ceramic Industry

基　　金：国家科技支撑计划(2013BAE03B01-10)。

摘　　要：为了研究采用凝胶注模法制备的氧化铝耐火材料的烧后性能与氧化铝微粉加入量的关系,以粒径的0.178-0.200 mm氧化铝为骨料,添加17%、33%、50%、67%比例的粒径0.04-0.10 mm的氧化铝微粉混合成固体混合粉,加入单体聚丙烯酰胺(AM),交联剂N,N-亚甲基双丙烯酰胺(MBAM),催化剂N,N,N’,N’,-四甲基乙二胺,分散剂聚丙烯酸钠配成料浆,固体混合粉占总重量的50%。使用高速混料机混合20min后加入引发剂过硫酸铵,注入直径50mm,高50mm的成型模具,经5min震动排气后放入60℃保温箱,试样表面硬化后脱模,将保温箱温度调至110℃,试样干燥64h后放入高温炉中加热至1600℃保温3 h。自然冷却至室温,测试材料的显气孔率、体积密度和强度,并通过扫描电镜观察微观结构。结果表明:在坯体形成阶段,随着氧化铝微粉的加入比例增加,单体在缩聚反应后生成的高分子长链就越长,形成的三维网状结构(骨架)就越完整,坯体的耐压强度数值越大;烧成后,随着氧化铝微粉的加入比例增加,试样的体积密度增加,显气孔率降低;微观相貌显示随着氧化铝微粉加入比例的增加,试样的基质与骨料的界面处的空隙数量趋于减小,界面趋于致密,微观结构越致密。This research has studied the relations of the properties of the alumina refractory after calcination with the amount of alumina addition prepared by means of gel casting. Samples are based on alumina of 0.178-0.2 mm as aggregates, alumina micro-powder of 0.04-0.10 mm, with 17 %, 33 %, 50 % and 67 % respectively, was mixed as solid blended powders, Then polyacrylamide(AM), N, N-methylene bisacrylamide(MBAM) as crosslink, N,N,N’,N’,-tetramethylethylenediamine as catalyst, sodium polyacrylate as dispersant were added as slurry, accounting for 50% of total weight. After 20 minutes of high-speed mixing, ammonium persulphate was selected as initiator, the powder was injected into mold with 50 mm in diameter, 50 mm in height. Then after vibrating for 5 minutes, the mould was put into incubator of 60 ℃. The temperature increased to 110 ℃ after demoulding process when the surface is hardening. After 64 h of drying process, samples were put into furnace and heated up to 1600 ℃ for 3 hours. When the samples cooled to room temperature, apparent porosity, bulk density and cold crushing strength were tested, SEM is employed to observe micro-structure. Results shows that during the period of growth in green brick, with the increase of addition amount of alumina micro-powder, polymer chain formed after the Polycondensation Reaction becomes longer, complete 3-dimendisonal network structure gives green brick superior crushing strength. After high-temperature burning, increase in addition amount of alumina micro-powder contributes to raised bulk density and reduced apparent porosity of samples;meanwhile, varies in addition percentage also changes micro phases, number of pores between matrix and aggregates tends to be decreased, this tendency imparts dense interface and micro-structure.

关 键 词：凝胶注模 氧化铝耐火材料 微粉粒度 性能 显微结构 

分 类 号：TQ174.75[化学工程—陶瓷工业]