Mo粉在球磨过程中的机械力效应

发布时间：2018-06-18 03:44

本文选题：Mo + 湿法球磨　；参考：《兰州理工大学学报》2017年03期

【摘要】：采用激光粒度分析仪、X射线衍射仪(XRD)和扫描电子显微镜(SEM)等分析仪器研究了Mo粉在机械球磨过程中粒度、晶粒尺寸和显微应变随球磨时间的变化规律.同时,探讨了机械球磨过程中Mo粉的显微结构特点及其细化机理.结果表明:在球磨初期Mo粉细化明显,球磨20h以后,Mo粉粒度细化趋于稳定,球磨30h后,平均晶粒尺寸达到18.19nm,体积平均粒径达到3.371μm,粒度分布曲线呈现为纳米、亚微米及微米区共存的3峰特征,晶粒尺寸与显微应变呈现ε=12.268 D~(-1.229)的逆变关系.其细化的机理是:球磨初期Mo粉产生强烈塑性变形,缺陷密度剧烈增加,粉体发生强烈加工硬化,加速了粉体碎化;球磨20h后冷焊和碎化达到动态平衡,粉体粒度趋于平稳.
[Abstract]:The variation of grain size, grain size and microstrain of Mo powder with ball milling time was studied by means of X-ray diffractometer (XRD) and scanning electron microscope (SEM) by means of laser particle size analyzer (LPA) and scanning electron microscope (SEM). At the same time, the microstructure characteristics and refining mechanism of Mo powder during mechanical ball milling are discussed. The results show that the grain size of Mo powder tends to be stable after 20 h ball milling, and the average grain size is 18.19 nm after 30 h ball milling, and the volume average particle size is 3.371 渭 m. The particle size distribution curve is nanometer. The three peaks of sub-micron and micron coexisted, and the relationship between grain size and microstrain was 蔚 _ (12.268) D ~ (-1) -1.229). The mechanism of refining is as follows: during the initial stage of ball milling, the Mo powder produces strong plastic deformation, the defect density increases sharply, the powder occurs strong work hardening and accelerates the powder fragmentation, the cold welding and shredding reach dynamic equilibrium after 20 hours of ball milling, and the particle size of the powder tends to be stable.
【作者单位】：兰州理工大学材料科学与工程学院;兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室;
【基金】：国家自然科学基金(51461029)
【分类号】：TB383.3;TG146.412

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