Synthesis and characterization of chromium carbide nanopowders processed by mechanical alloying assisted microwave heating route

• Cr3C2 nanopowders were prepared at relatively low temperature.
• The synthesis method is mechanical alloying assisted microwave heating.
• The method contributes to the formation of a well dispersed carbide nanopowders.
• The powders show good dispersion with a mean particle size of about 50 nm.

Chromium carbide nanopowders were synthesized via mechanical alloying assisted microwave heating route using micron-sized chromic oxide (Cr2O3) and nano-sized carbon black as raw materials. The samples were characterized by X-ray diffractometry (XRD), thermogravimetric and differential scanning calorimetry (TG-DSC), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The results show that the ultimate weight loss revealed by TG curve is 47.6 wt%. The transformation temperature (1030 °C) of the mixture after mechanical alloying is much lower than that of the traditional mixing method (1122 °C). Chromium carbide nanopowders have been successfully synthesized at 1000 °C for 1 h. The powders show good dispersion and are mainly composed of spherical or near-spherical particles with a mean diameter of about 50 nm. Compared with the traditional carbon thermal reduction method, the reaction temperature and time synthesized by mechanical alloying assisted microwave heating method can be reduced and shortened by 400 °C and 3 h, respectively.