Investigation of the Effects of Oven-Chemical and Mechanically Activated Techniques on the In Situ Synthesis of MoSi₂-SiC Nanocomposites by Self-Propagating High-Temperature Synthesis

The purpose of this study was to investigate suitable methods for the one-step synthesis of MoSi₂-SiC nanocomposites by self-propagating high-temperature synthesis. Therefore, oven-chemical and mechanically activated techniques were selected from the available options. First, the elemental raw materials molybdenum (Mo), silicon (Si), and graphite (C) were mixed in powder form and milled in stoichiometric ratios in a planetary mill for ۰, ۱, ۳, and ۶ h at a ball-to-powder ratio (BPR) of ۱۰:۱ and a rotational speed of ۲۵۰ rpm. The resulting powder was compacted in a uniaxial press at ۳۰۰ MPa. In parallel, combustion-aid samples were prepared using Mo-Si-Al raw materials. In the next step, the main samples (Mo-Si-C) and the combustion-aid samples (Mo-Si-Al) were assembled together and transferred to the combustion reactor at a temperature of ۸۵۰ °C in an Ar atmosphere. After synthesis in the reactor, the samples were characterized by TEM, SEM, and XRD. Finally, a MoSi₂-SiC nanocomposite with crystallite sizes below ۱۰۰ nm and the fewest undesirable phases was synthesized in situ from elemental raw materials by optimizing the parameters affecting the self-propagating high-temperature synthesis process.

کلیدواژه ها:

Nanocomposite ، MoSi۲-SiC ، SHS ، Mechanical- Activated ، Oven-Chemical