Al–Al2O3 core–shell composite by microwave induced oxidation of aluminium powder

Microwave processing is gaining importance in the preparation of composite materials mainly because of its predominance in the improvement of uniformity for different phases formed. In the present study, commercial Al powder was heat treated using microwave radiation to synthesize Al–Al2O3 core–shell composite powder. The as received Al powder and the microwave heated Al powders were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and zeta potential measurement. XRD data confirmed the formation of Al–Al2O3 composite. FTIR studies indicated the core–shell type Al–Al2O3 composite formation. SEM observations suggested the formation of Al–Al2O3 core–shell composite. TEM images, corresponding selected area electron diffraction (SAED) patterns and EDX analysis confirmed the Al–Al2O3 core–shell composite development. Zeta potential measurements also indicated that Al core particles were surrounded with Al2O3 shell.