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借助X射线衍射和透射电子显微镜研究了在机械驱动下难熔金属Ta与N2 的氮化反应 .实验发现 ,在室温下的高能球磨可实现Ta N2 反应 ,并形成三种不同结构的氮化物 :六方结构的Ta2 N ,四方结构的Ta3 N5和非晶相 .研究表明 ,N2 在清洁的金属表面上发生可离解式的化学吸附是Ta N2 反应的基本过程 ,高的Ta—N键合能是N2 分子在Ta表面上发生化学吸附的热力学驱动力 ,而球磨在金属粉末中引入的储能 (界面能和缺陷能 )为Ta—N向金属氮化物转变提供了激活能 .球磨后期非晶相的形成则源于Fe的侵入 ,所形成的非晶相含有Ta Fe N三种元素 .
The nitridation reaction of Ta and N2, a refractory metal under mechanical driving, was studied by means of X-ray diffraction and transmission electron microscopy. It was found that high energy ball milling at room temperature can achieve Ta N2 reaction and form three kinds of nitride with different structures: Ta2N with hexagonal structure, Ta3N5 with tetragonal structure and amorphous phase.Research shows that dissociative chemisorption of N2 on the clean metal surface is the basic process of TaN2 reaction, and the high Ta-N bond energy is N2 molecular thermodynamic driving force on the surface of Ta chemisorption, and ball mill introduced in the metal powder storage energy (interface energy and defect energy) for the transformation of Ta-N to metal nitride activation energy provided by the post-milling amorphous phase Formed from the invasion of Fe, the amorphous phase formed contains Ta Fe N three elements.