WANG Xiaojun 1, YAN Xia 1, LIU Yan'e 1, WANG Ling 1, SU Tinglong 2, TIAN Yuming 3
(1. Department of Physics and Electronic Information Engineering, Lyuliang University, Lvliang 033001, Shanxi, China;
2. Xiaoyi King Kong Refractory Co., Ltd, Lvliang 032200, Shanxi, China; 3. School of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, Shanxi, China)
Abstract: MgAl2O4-CaAl12O19 composites have attracted much attention because of their excellent properties, which have applications in some special high-temperature industries. In this paper, with ore powders of bauxite, dolomite and magnesite as raw materials, MgAl2O4-CaAl12O19 composites were obtained by using solid-phase sintering process at 1100–1500 ℃ for 2 h. The effects of the content of bauxite and sintering temperature on phase composition, microstructure and mechanical properties of the composites were studied. The optimal densification was observed when the sintering temperature was 1500 ℃ and the bauxite content was the largest, with a bulk density of 2.68 g·cm−3 and an apparent porosity of 11%. The corresponding flexural strength was 113.63 MPa, when the mass ratio of MgAl2O4 and CaAl12O19 was 1.82.
Key words: bauxite; composites; calcium hexaluminate; phase composition; mechanical properties; solid solution