CNTs辅助球磨对Zr粉形貌和氧化性能的影响（英文）

发布时间：2018-05-30 20:18

  本文选题：Zr粉 + 球磨　； 参考：《稀有金属材料与工程》2017年09期

【摘要】：研究了不同球磨时间条件下CNTs辅助球磨对Zr粉形貌和氧化性能的影响。采用XRD和SEM分析了球磨过程中Zr粉的物相组成和形貌演变,采用热重(TG)法评估了Zr粉的氧化性能。结果表明:添加CNTs辅助球磨对Zr粉的物相组成没有影响,但是会影响Zr粉的形貌和氧化性能。不添加CNTs时,随着球磨时间的增加(1~3 h),Zr粉粒径持续减小,球磨3 h后,Zr粉粒径由十几微米减小到2~3μm。添加CNTs辅助球磨后,Zr粉的颗粒细化过程滞后,球磨初期(1~2 h),Zr粉粒径没有显著变化,直到球磨时间延长到3h时,Zr粉粒径才开始明显减小。这是因为CNTs在Zr颗粒表面的黏附和CNTs在Zr粉中的团聚阻碍了磨球对Zr颗粒的机械冲击和破碎作用。与直接球磨Zr粉相比,当所得Zr粉粒径相差不大时,添加CNTs辅助球磨使Zr粉的起始氧化温度和峰值氧化温度降低了11~37℃,这是因为CNTs的良好导热性促进了Zr粉氧化过程中的传热。另一方面,球磨时间少于2 h时,Zr/CNTs混合物中Zr粉的氧化增重量比纯Zr粉的增重量略有降低,但球磨时间超过2 h时,这种趋势出现反转。前者是因为短时间球磨时,CNTs引起Zr粉的局部团聚,阻碍了团聚体中Zr粉与氧气的接触,并且混合物中的Zr粉颗粒还没有被明显细化,这都降低了Zr粉的氧化程度;随后的反转趋势是因为球磨时间增加后,混合物中的Zr粉开始明显细化,促进了其氧化反应的进行,但是纯Zr粉由于颗粒尺寸提前细化而发生了显著的自发氧化,降低了活性Zr的含量。
[Abstract]:The effects of CNTs assisted ball milling on the morphology and oxidation properties of Zr powder under different milling time were studied. The phase composition and morphology evolution of Zr powder during ball milling were analyzed by XRD and SEM. The oxidation properties of Zr powder were evaluated by thermogravimetric method. The results show that the addition of CNTs has no effect on the phase composition of Zr powder, but it will affect the morphology and oxidation performance of Zr powder. When CNTs was not added, the particle size of Zr powder decreased with the increase of milling time, and decreased from 10 micron to 2 渭 m after 3 h ball milling. The grain refinement process of Zirconium powder after adding CNTs was delayed, but the particle size of Zirconium powder did not change significantly at the initial stage of ball milling, but only began to decrease obviously when the milling time was prolonged to 3 h. This is due to the adhesion of CNTs on the surface of Zr particles and the agglomeration of CNTs in Zr powder, which hinders the mechanical impact and fragmentation of grinding balls on Zr particles. Compared with the direct ball milling Zr powder, the initial oxidation temperature and the peak oxidation temperature of the Zr powder decreased by 11 ~ 37 鈩，

本文编号：1956636