X-ray Powder Diffraction Method is Used to Determine Substantial Phase Composition of TiO_2 at Different Temperatures

：X-ray powder diffraction method is used to determine substantial phase composition of TiO2 at different temperatures.Also unmarked method and multiphase direct analysis method are adopted to analyse the result of the experiment, consequently they are the same. At the normal atmospheric temperature or 700℃ and to preserve the heat for five hours, TiO2 remains only one crystal shape —anatase; while at 1000℃ and to keep the temperature for five hours,1.3% TiO2 has turned into rutile; if adding the temperature up to 1090℃,also keeping the heat for five hours,80.1% TiO2 has changed from anatase to rutile.