Synthesis of chromium carbide nanopowders via a microwave heating method

• Published in: International journal of refractory metals & hard materials 2015-07, Vol.51, p.212-215
• Main Authors: Zhao, Zhiwei, Chen, Feixiao, Wang, Mingchao, Zheng, Hongjuan
• Format: Article
• Language: English
• Subjects: Chromium carbide; Chromium oxides; Heat treatment; Low temperature; Microstructure; Microwave heating; Microwaves; Nanopowders; Nanostructure; Scanning electron microscopy; Synthesis; Transmission electron microscopy
• ISSN: 0263-4368; 2213-3917
• DOI: 10.1016/j.ijrmhm.2015.04.010

Chromium carbide nanopowders were firstly synthesized via a simple microwave heating technique using nanometer chromic oxide (Cr2O3) and nanometer carbon black as raw materials in argon gas atmosphere. The samples were characterized by X-ray diffractometry (XRD), thermogravimetric and differential scanning calorimetry (TG–DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The results show that chromium carbide nanopowders with an average crystallite size of 24nm can be synthesized at 1000°C for 1h. The synthesis temperature required by the method is 400°C lower than those required by the conventional approaches for preparing chromium carbide. SEM and TEM results show that the powders show good dispersion and are mainly composed of spherical or nearly spherical particles with a mean diameter of about 30nm. The phase transformation sequence during the heat treatment is: Cr2O3→CrO→Cr7C3→Cr2C→Cr3C2. •Chromium carbide nanopowders were firstly prepared by microwave heating method.•The synthesis temperature is 400°C lower than those of conventional methods.•The powders show good dispersion and a lower particle size of about 30nm.