Facile synthesis of MgAl2O4 spinel matrix nanocomposite with TiC, AlTi3, and Al2O3 reinforcements by mechanical alloying

Abstract

MgAl₂O₄ spinel matrix nanocomposite with TiC, AlTi₃, and Al₂O₃ was directly fabricated using the mechanical alloying (MA) method with Mg, TiO₂, Al, and graphite as the starting powder mixture. This methodology was used to synthesize magnesium aluminate spinel (MSA) matrix nanocomposite with having the advantage of no subsequent heat treatment. The mixture of the powders was milled at room temperature using a high-energy planetary ball mill with a vial rotation speed of 400 rpm in the air. The phases and morphological analysis after the MA process were characterized by X-ray diffraction and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS). Followed by 20 h of ball-milling, all the desired phases of MgAl₂O₄, TiC, AlTi₃, and Al₂O₃ appeared in XRD results, and also a small fraction of raw materials remained. The major reactions to synthesize MgAl₂O₄/TiC-AlTi₃-Al₂O₃ spinel matrix nanocomposite were the reduction of TiO₂ by Al and Mg.