Articles
  • Developing Al2O3-TiC in-situ nanocomposite by SHS and analyzingtheeffects of Al content and mechanical activation on microstructure
  • A. Masoudiana, M. Karbasib, F. SharifianJazia,* and A. Saidib
  • a Mining and Metallurgical Engineering Department, Amirkabir University of Technology, P. O. Box 15875 4413, Tehran, Iran b Materials Engineering Department, Isfahan University of Technology, Isfahan 84154-83111, Iran
Abstract
Al2O3-TiC in-situ nanocomposite was developed by self propagating high temperature synthesis (SHS) process using TiO2, Al and C powders as starting materials. The effects of mechanical activation and Al content on the reaction mechanisms and microstructures of products were investigated and thermodynamic and kinetic aspects of reactions were evaluated. Samples were characterized by X-Ray diffraction (XRD), scanning electron microscopy, (SEM)and Energy Dispersive Spectroscopy (EDS). According to the findings,increasing Al content of reactants led to enhancing the heat transfer and avoiding heat outlet by omitting CO as gas product. Also,mechanical activation resulted in better distribution of the initial materials, a decrease inthe diffusion distance, and in better kinetics of the combustion synthesis reaction at lower temperature. Consequently, ceramic matrix nanocomposites (CMNC) with phase size less than 800 nm and crystalline size less than 65 nm were developed.

Keywords: Self propagating high temperature synthesis (SHS), Ceramic matrix nanocomposite (CMNC), Mechanical activation (MA), Thermodynamic, Kinetic.

This Article

  • 2013; 14(4): 486-491

    Published on Aug 31, 2013