Sintering Performance of MgAl2O4 Spinel with Various Al2O3 Content

Magnesium aluminate spinel specimens with various Al2O3 content were prepared. Sintering performance and microstructure of different kinds of MgAl2O4 spinel were studied. It is found that the sintering of materials becomes more difficult with the increase in their Al2O3 contents. Corundum begins to precipitate from the magnesium aluminate spinel with 85wt% Al2O3 at 1400. However, with further increase in the sintering temperature, the corundum dissolves into magnesium aluminate spinel (above 1600). The precipitation and solid solution of corundum hinder the sintering of materials. In alumina-rich spinel, if the content of Al2O3 in alumina-rich spinel materials is more and the content of CA6 is also more. At the same time CA6 crystal is bigger in the alumina-rich spinel.