热等离子体反应合成WC超细粉体

Synthesis of Superfine WC Powders in Thermal HF-plasma Reactor

用不同的工艺方法,以固体钨酸颗粒为钨源,乙炔气体或石墨粉为碳源,在高频等离子体反应炉中合成WC超细粉体。比较了固 气和固 固反应体系的产物组分和反应过程,探讨了加氢工艺对反应过程及产物的影响。研究表明,钨酸与石墨粉的反应效率高于与乙炔气体的反应效率,可以获得含量大于80%、粒度在0.5μm以下的WC超细粉体。

The results of preparation of superfine tungsten carbide (WC) powders in a 30kW thermal HFplasma reactor for the systems of tungstenic acid (H2WO4) + graphite and tungstenic acid (H2WO4) + acetylene (C2H2) are presented in the paper. To promote the yield of WC powders, hydrogen gas as reactive intermedium and heat transmitting agent, was introduced to the reactive process. Scanning Electron Microscope (SEM), Xray Diffracter (XRD) and located Energy Dispersion Spectrometer(EDS) were employed to characterize the morphology, crystalline structure and composition of the powders. A thermaldynamic analysis of the possible reactions and the behavior of raw materials in flow gas at high temperature were performed, to explain why a better result was got in the solidsolid reaction system.