Synthesis and formation mechanism of W/TiC composite powders by a wet chemical route

摘要

W/TiC composite powders were prepared through a novel wet chemical method using ammonium paratungstate and nanosized TiC powders as raw materials. The as-synthesized powders were characterized by X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and energy-dispersive spectroscopy. The as-synthesized powders possessed a uniform diameter of about 30 nm to 100 nm and contained only nanosized W and TiC particles. TEM images and diffraction ring spectra confirmed that the "cluster" structure composite powders are composed of TiC and nanosized W particles, which are located on the surface of TiC particle. To observe the formation of this structure, we focused on the process of preparing W/TiC powder and proposed a reasonable mechanism for the formation of the second-phase doped in W matrix materials by wet chemical method. The method followed an ideal model that may be used to prepare other materials. (C) 2015 Elsevier B.V. All rights reserved.