Effect of TiO_2 on Mechanical Properties and Microstructure of Magnesium Aluminate Spinel Refractories

摘要

MgO-Al_2O_3-TiO_2 composite refractories were prepared by using magnesium aluminate spinel (MgAl_2O_4) and titanium dioxide as main starting materials and being sintered at high temperature. The influences of titanium dioxide additions on the room temperature physical properties, phase composition and microstructure were investigated. The phase composition and microstructure were tested by means of XRD and SEM. The results revealed that with increasing TiO_2 content, the densification of the composites first increased sand then decreased and maximized at 4% TiO_2 loading. This showed appropriate amount of TiO_2 could contribute to the sintering of the composites due to the solid solution of TiO_2 in magnesium aluminate spinel.