Abstract: To study the effect of the slurry solid loading on their properties,lightweight calcium hexaluminate materials were prepared using active alumina (d₅₀=1.9 μm) and calcium hydroxide (d₅₀=4.3 μm) as starting materials by foaming-gel casting.The effects of the solid loading in the slurry (50%,52.5%,55%,57.5% and 60%,by volume,respectively) on the phase composition,the microstructure and the properties of the fired samples were studied.The results show that after high temperature treatment,flake calcium hexaluminate crystals in the samples prepared by foaming-gel casting are interwoven to form a large number of micropores smaller than 5 μm,accounting for more than 50% of total pores.In this study,with the solid loading of 57.5%,the sample has the best properties,performing the cold compressive strength of 9.4 MPa.

Key words: calcium hexaluminate, solid loading, microstructure, compressive strength

摘要： 为研究浆体固含量对六铝酸钙轻质材料性能的影响,以d₅₀=1.9 μm的α-Al₂O₃和d₅₀=4.3 μm的Ca(OH)₂为原料,通过发泡法-凝胶注模工艺制备六铝酸钙轻质材料,研究了浆体中固含量(φ,分别为50%、52.5%、55%、57.5%、60%)对烧后试样物相组成、显微结构和性能的影响。结果表明:通过发泡法-凝胶注模工艺制备的试样在高温处理后,试样中片状六铝酸钙晶体相互交织形成大量孔径小于5 μm的微孔,此类微孔占总气孔数量的50%以上。在本研究中,当浆体中固含量为57.5%(φ)时,六铝酸钙轻质材料性能最佳,其常温耐压强度达9.4 MPa。

关键词: 六铝酸钙, 固含量, 显微结构, 耐压强度