Synthesis and microstructure of tantalum carbide and carbon composite by liquid precursor route

A new technology for preparing tantalum carbide materials is reported. Phase compositions and microstructures were characterized by X-ray diffraction and scanning electron microscopy, respectively. Ta₂O₅ microcrystallites are formed after carbonization, and after high-temperature treatment Ta could be almost transformed into cubic TaC. As temperatures rise, the graphitization degree of carbon matrix increases and the grain sizes of TaC particles obviously enlarge. TaC is formed through a carbothermal reduction reaction between Ta₂O₅ and C, following the liquid phase reaction and 'diffusion-aggregation' mechanism.