莫来石纤维增强氧化物多孔陶瓷及其性能研究  

Preparation and Properties of Mullite Fiber Reinforced Oxide Porous Ceramics

作　　者：黄泽[1] 邓承继[1] 董博 余超[1] 丁军[1] 朱青友[1] 祝洪喜[1] 王奕博 HUANG Ze;DENG Chengji;DONG Bo;YU Chao;DING Jun;ZHU Qingyou;ZHU Hongxi;WANG Yibo(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《陶瓷学报》2024年第3期508-514,共7页Journal of Ceramics

基　　金：湖北省重点研发计划项目(2023BAB106);国家自然科学基金(U21A2057)。

摘　　要：以不同规格的粉煤灰漂珠、长石粉和铝矾土粉为主要原料,引入莫来石纤维为增强相,研究莫来石纤维含量对多孔陶瓷材料性能的影响规律及作用机理。结果表明:高温下长石粉中的低熔相能够降低材料的共晶熔点,将基质间的物理界面结合转变为化学结合。样品经1100℃烧成后,随着莫来石纤维含量的增加,多孔陶瓷的闭口气孔率增加,而常温耐压强度和体积密度呈现先增大后减小的趋势。当莫来石纤维含量为10 wt.%时,材料具有最佳综合性能,其体积密度为(0.74±0.01)g·cm^(−3)、真气孔率为(72.70±0.58)%,常温下耐压强度为(7.30±0.64)MPa。此外,试样在300℃、600℃及900℃下的平均热导率分别为0.202 W·m^(−1)·K^(−1)、0.214 W·m^(−1)·K^(−1)及0.244 W·m^(−1)·K^(−1)。Fly ash cenospheres,feldspar powder and alumina powder with various specifications were utilized as the raw materials and mullite fibers were introduced as a reinforcing phase to fabricate porous ceramics.The effect of mullite fiber on properties of the porous ceramics and the mechanism were studied.It is indicated that the incorporation of low-melting phases from feldspar powder at high temperatures was employed to reduce the eutectic point of materials,transforming the physical interface between the matrix phases into a chemical bond.An increase in mullite fiber content led to rise in closed porosity of the porous ceramics after sintering at 1100℃.Simultaneously,room-temperature compressive strength and bulk density initially increased and then decreased with rising content of mullite fiber.Optimal comprehensive performance was achieved when the mullite fiber content was 10 wt.%,resulting in a volume density of(0.74±0.01)g·cm^(−3),a true porosity of(72.70±0.58)%,and a room-temperature compressive strength of(7.30±0.64)MPa.In addition,average thermal conductivities of the specimens at 300℃,600℃and 900℃were 0.202 W·m^(−1)·K^(−1),0.214 W·m^(−1)·K^(−1)and 0.244 W·m^(−1)·K^(−1),respectively.

关 键 词：粉煤灰漂珠 莫来石纤维 多孔陶瓷材料 液相烧结 高温热导率 力学性能 

分 类 号：TQ174.75[化学工程—陶瓷工业]