Effect of co-doping manganese oxide and titania on sintering behaviour and mechanical properties of alumina

The effect of co-doping of titania and manganese oxide at different weight percentages (0.5-5 wt%) on sintering behaviour and mechanical properties of alumina were evaluated. The undoped and doped alumina were pre -pared through pressureless sintering which was carried out at different temperatures (1000 degrees C-1500 degrees C) and were characterized through XRD and SEM. XRD revealed presence of R-TiO2 and alpha-alumina at low sintering temperature which further reacted to form Al2TiO5 at sintering temperature above 1350 degrees C. Manganese oxide (MnO2) was not reactive with alumina due to atomic radii mismatch. SEM indicated abnormal grain growth with increase in sintering temperature and dopant composition. The addition of doping led to reduction in the sin -tering temperature with high relative density (-98%) and enhanced mechanical properties (E = 370 GPa and HV = 14.8 GPa) which was only achievable by undoped alumina by sintering at higher temperature regime.

Automated summary

The effect of co-doping of titania and manganese oxide at different weight percentages on sintering behaviour and mechanical properties of alumina were studied. The addition of doping reduced the sintering temperature and improved the density and mechanical properties of alumina. XRD analysis revealed the formation of R-TiO2 and alpha-alumina at low sintering temperature, which further reacted to form Al2TiO5 at higher sintering temperature. MnO2 did not react with alumina due to atomic radii mismatch. SEM showed abnormal grain growth with increasing sintering temperature and dopant composition.