Synthesis and Characterization of γ-Al2O3 Nano Powder by Disc Milling of Al and MnO2 Powder

Nano-sized alumina particles have been generated by milling mixture of aluminium and manganese dioxide powders mixed in ratio of 1:7 by weight in a vibratory disc mill for different milling time of 450, 600 and 750 min. The mill was operated at 700 rpm. High energy milling of manganese dioxide particles with excess of aluminium powder ensures that nanoparticles generated, either of MnO2 or alumina, are mostly separate and surrounded by aluminium particles. The structural changes of powder particles during mechanical alloying were studied by X-ray diffraction, scanning electron microscopy and TEM. In the mixture of milled powders with particle size in the range 10 to 200 nm. The addition of toluene was used as the process control agent to avoid severe agglomeration appears to be efficient to enhance the milling effect.