Kinetics of Fe2O3-Al reaction prior to mechanochemical synthesis of Fe3Al-Al2O3 nanocomposite powder using thermal analysis

Journal of Nanoanalysis

مقالات آماده انتشار، پذیرفته شده، انتشار آنلاین از تاریخ 01 خرداد 1398

نوع مقاله: Original Research Paper

شناسه دیجیتال (DOI): 10.22034/jna.2019.1868002.1140

نویسنده

Mehdi Khodaei^*

Faculty of Materials Science and Engineering, K.N. Toosi University of Technology, Tehran, Iran

چکیده

The effect of ball milling on kinetics of the thermite reaction of 3Fe2O3 + 8Al powder mixture to synthesize Fe3Al-Al2O3 nanocomposite was investigated using differential thermal analysis. A model-free method was applied to the non-isothermal differential calorimetry (DSC) data to evaluate the reaction kinetics according to the Starink method. The activation energy of the thermite reaction in the Fe2O3-Al system in ball milled 3Fe2O3 + 8Al powder mixture was determined to be 97 kJ/mole, which is smaller than that for non-milled powder mixture indicating the change of reaction mechanism. The change in the reaction mechanism could be resulted from the formation of short-circuit diffusion paths occurring in the precursors during milling. The change in the reaction mechanism of such nanostructured 3Fe2O3 + 8Al powder mixture could be reason of the formation of desired phases (Fe3Al and Al2O3), which such stoichiometric phases cannot be achieved by conventional molten state thermite reaction.

کلیدواژه‌ها

Kinetics؛ Differential Scanning Calorimetry (DSC)؛ Mechanochemical؛ nanocomposite؛ Fe3Al-Al2O3