球磨环境对机械合金化合成纳米TiC的影响

以Ti粉和活性炭粉作为原始粉末在行星式球磨机(QM ISP2)上进行高能球磨,分别在低真空、高真空、Ar、空气+H2和H2等不同球磨环境下机械合金化合成TiC。采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等技术对合成产物进行物相和形貌分析,并用热力学和Maurice Courtney模型等理论对其合成机理进行了探讨。结果表明,在5种不同球磨环境下用Ti粉和活性炭粉都能合成TiC,其中在H2环境下的合成速度最快。H2对TiC的机械合金化合成具有加速作用,其机理是H2不仅能促使Ti与活性炭粉末细化,使断裂的新鲜表面保持清洁,而且能使Ti的活性增强。

Effects of milling atmospheres on synthesis of nanometer-sized titanium carbide by mechanical alloying

A high-energy ball milling was operated in planetary ball mill machine, starting from element titanium (Ti) and active carbon(C) powders. The X-ray diffraction(XRD), scanning election microscopy (SEM) and transmission election microscopy were applied to study the synthesis products of mechanical alloying under low vacuum, high vacuum, Ar, air+H_2 and H_2 milling atmospheres. The synthesis mechanism was discussed through thermodynamics and Maurice-Courtney model. The results show that element titanium and active carbon powders can be synthesized TiC under above milling atmospheres, and the synthesis speed is the fastest under H_2 atmosphere. H_2 has the tendency of accelerating synthesis. And the mechanism is that H_2 can not only accelerate the refinedness of the powder particle of Ti, make the novel surface of fracture clean, but also enhance the activation of Titanium.