Effect of microwave processing on polymorphic transformation of TiO2

Microwave (MW) processing for ceramics is gaining attention all over the world due to its inherent advantages. In this paper, we have attempted to examine the influence of microwave heating on polymorphic phase transformation of titanium dioxide from anatase to rutile. The results are compared with those obtained by heating the same samples in resistance heated furnace under identical conditions. The study indicated that in the microwave heating, complete transformation of pure anatase phase to rutile takes place at lower temperature (900 °C, 30 min dwell time) compared to only partial conversion (<60%) to rutile when the same sample is heated in conventional resistance furnace at 1000 °C for 30 min. The results obtained further show that the presence of rutile phase in the anatase sample considerably accelerates its transformation to rutile irrespective of the mode of heating (i.e. microwave or resistance heating) adopted in the experiment.