DENSIFICATION OF ALUMINA AT 1250-DEGREES-C WITH MNO2 AND TIO2 ADDITIVES

The effects of MnO2 and TiO2 additions in 3 wt% MnO2 + (0.5, 1.5, 3.0) wt% TiO2 additive combinations on the sintering of alpha-Al2O3 have been investigated. The microstructural development along with the microhardness has been characterized. The Al2O3 + 3 wt% MnO2 + 0.5 wt% TiO2 system resulted in high densification (98% of the theoretical density) giving a uniform grained microstructure and yielding a hardness value of 23.14 GPa at a sintering temperature as low as 1250 degrees C.