以钢渣和尾矿为主要原料的多孔陶瓷制备机理

Reaction Mechanism of Porous Ceramics Prepared from Steel Slag and Bauxite Tailings

摘要: 以转炉钢渣、铝土矿尾矿为主要原料，利用混合造粒方法制备陶瓷原料颗粒，并进一步经压制成型、高温烧结，制备了多孔陶瓷。利用Ｘ射线衍射仪、金相显微镜和扫描电子显微镜表征了多孔陶瓷的物相组成和微观结构，并分析了多孔陶瓷显气孔率及抗折强度在烧结过程的变化规律。研究表明：钢渣掺入量为30 wt%时，多孔陶瓷中以辉石、钙长石为主晶相，提高烧成温度会促进材料的致密化，使得较小孔隙的颗粒之间发生连接，多孔陶瓷显气孔率降低和抗折强度升高；同时，未能排除的较大孔隙则保留下来形成了三维多孔贯通结构。本实验条件下的多孔陶瓷最佳烧结温度为1140℃时，此时孔径大小从数十微米到数百微米分布，性能优异，其抗折强度达到12.86 MPa，显气孔率为21.48%。

Abstract: Raw particles were prepared via granulation process from steel slag and bauxite tailing, and porous ceramics were prepared after mould and sintering from the particles. Effect of sintering temperature on the apparent porosity and bending strength of porous ceramics samples were in-vestigated. Its phase composition and microstructure were characterized by X-ray diffractometer, metallographic microscopy and scanning electron microscope. The results indicated that pyroxene and anorthite were the main crystal phases in the porous ceramics with content of 30 wt% steel slag. Increasing the sintering temperature, porous ceramics would had a reduced apparent porosity and enhanced bending strength during densification process, while the remained larger pores formed in preparation process of ceramic green kept 3-dimension porous structure. In this study, the optimum sintering temperature for the porous ceramics was 1140˚C, and the sample had a porosity of 21.48%, excellent bending strength of 12.86 MPa.