球磨方式对制备(Ti,15W,5Mo,0.2V)(CN)-20Ni复合粉相结构的影响

Effects of ball milling modes on phase structure of (Ti,15W,5Mo,0.2V)(CN)-20Ni composite powders during reaction synthesis

利用X衍射仪研究了滚筒球磨和高能球磨后的混合料经碳热还原氮化制备(Ti,15W,5Mo,0.2V)(CN)-20Ni复合粉工艺过程中的物相演变。结果表明,普通滚筒球磨混合方式下的混合体系遵循TiO2→Ti3O5→Ti(ON)→Ti(CN)的相转变规律;而高能球磨混合方式下混合料的衍射峰普遍宽化,物料细化,活性提高,其中以高能球磨干混的效果最佳,其在1200℃即可获得无杂相的(Ti,15W,5Mo,0.2V)(CN)-20Ni复合粉,且反应过程未出现Ti(ON)中间相;另外在不同球磨方式下,随着Ti(CN)的形成,均有大量W、Mo、V等原子从Ni固溶体相中析出,并扩散进入Ti(CN)的晶格形成(Ti,W,Mo,V)(CN)固溶体。

The （Ti, 15W, 5Mo, 0.2V）（CN）-20Ni composite powders were prepared by oxides via tumbling ball milling and high-energy ball milling and subsequent carbothermal reduction nitridation. And then X-ray diffractometry （XRD） was adopted to analyze the phase composition of the milled mixtures or composite powders. The results show that the phase evolution sequences of TiO2 followed in the reaction process are.TiO2→Ti3O5→Ti（ON）→Ti（CN） for tumbling ball milling. But the diffraction peaks of the milled mixtures become wider and the reaction activation of powders are improved by high-energy ball milling, especially without solvent. For the high-energy milled mixtures,Ti（ON） phase does not occur during reaction synthesis and the composite powders of （Ti, 15W, 5Mo,0.2V）（CN）-20Ni without impurity phase are synthesized at only 1200℃. In every ball milling mode,many W,Mo and V atoms precipitate from Ni solid solution with the formation of Ti（CN） and subsequently dissolve into Ti（CN） structure to form （Ti,W,Mo, V）（CN） solid solution.