Synthesis kinetics of Mg2Si and solid-state formation of Mg–Mg2Si composite

The synthesis kinetics of Mg2Si intermetallic compounds (IMC) from the elemental mixture of Mg–Si powders was studied by using differential thermal analysis (DTA). The exothermic peaks were at 818 K, which indicated the synthesis reaction of 2 Mg + Si → Mg2Si. The synthesis kinetics of Mg2Si was evaluated by the Ozawa method and KAS method, and its activation energy was calculated as 377.53 KJ/mol. Based on the data from DTA curves, the bulky materials of Mg–Mg2Si composite were prepared through solid-state reaction by using SPS consolidation process. From the results of XRD and SEM-EDS analysis on the composite materials, it was clarified that at low temperatures of 813 K and 833 K, Mg and Si powders never react completely, and the suitable temperature of solid-state synthesis by SPS should be about 853 K.