Effects of technical factors on MgAl2O4–TiN composites produced by aluminothermic reduction and nitridation

MgAl2O4/TiN composites were formed by aluminothermic reaction between Al, TiO2, and MgO powders in nitrogen gas. The effects of addition of graphite, α-Al2O3 into mixtures 8Al–6TiO2–4MgO, and shaping pressure on the synthesized composites was investigated by X-ray diffraction. The results showed that: addition of graphite can lead to formation and lattice parameters change of Ti(C, N). When α-Al2O3 powder was added into mixtures 8Al–6TiO2–4MgO, theoretic spinel transformed into alumina-rich spinel and lattice parameters of the spinel became low. Inadequate N2 gas caused by higher shaping pressure can give rise to the formation of intermediate product Al3Ti alloy in the synthesis of the composites.