摘要
以纳米η-Al2O3粉为铝源,石英粉、硅灰,白泥和复合粉(白泥︰石英粉=25︰75)为硅源,通过固相反应烧结原位合成莫来石材料。研究了不同硅源及温度对试样的烧结性能,物相组成和显微结构的影响,分析了莫来石的合成机理。结果表明:在1550℃保温3 h时,以白泥为硅源的试样性能最佳,体积密度为2.86 g/cm3,显气孔率为3.5%,抗折强度为135.6 Mpa;除白泥外纳米η-Al2O3粉与其他三种硅源所制备的试样全部为莫来石相衍射峰;以石英粉和硅灰为硅源制备的莫来石晶体为短柱状,抗折强度相对较小,以白泥和复合粉为硅源制备的莫来石晶体为长柱状,抗折强度相对较大;纳米η-Al2O3与白泥中分解出来的无定形Si O2反应形成莫来石,在转成α-Al2O3后与石英粉和硅灰中Si O2反应合成莫来石。
Mullite materials were in-situ synthesized by solid state reaction sintering using nano-η-Al2O3 powder as aluminum source,quartz powder,silica fume,white mud(soft clay)and composite powder(white mud︰quartz powder=25︰75)as silica source.The effects of different silicon sources and temperatures on the sintering properties,phase composition and microstructure of the samples were investigated,and the synthesis mechanism of mullite was analyzed.The results show that the sample with white mud as silicon source has the best properties at 1550℃for 3 hours.Its bulk density is 2.86 g/cm3,the apparent porosity is 3.5%,and the flexural strength is 135.6 MPa.The samples prepared by nano-η-Al2O3 powder and other three silicon sources except white mud are all mullite phase diffraction peaks.The sample mullite crystals prepared from quartz powder and silica fume are short columnar with relatively low flexural strength,while the sample mullite crystals prepared from white mud and composite powder are long columnar with relatively high flexural strength.Nano-η-Al2O3 reacts with amorphous SiO2 separated from white mud to form mullite,and then reacts with Si O2 in quartz powder and silica fume to synthesize mullite.
作者
李凤友
张玲
常雅楠
苏鑫
张志豪
张欢
LI Fengyou;ZHANG Ling l;CHANG Yanan;SU Xin;ZHANG Zhihao;ZHANG Huan(School of materials and metallurgy,Liaoning University of Science and Technology,Anshan 114051,Liaoning,China;Shandong Refractories Group Lunai Kiln Refractories Co.,Zibo 255200,Shandong,China;Research Institute of Refractories,Yingkou Qinghua Group,Yingkou 115100,Liaoning,China)
出处
《陶瓷学报》
CAS
北大核心
2019年第6期750-756,共7页
Journal of Ceramics
基金
国家自然科学基金(51702144)
