發(fā)布時間：2018-05-30 20:18

  本文選題：Zr粉 + 球磨　； 參考：《稀有金屬材料與工程》2017年09期

【摘要】：研究了不同球磨時間條件下CNTs輔助球磨對Zr粉形貌和氧化性能的影響。采用XRD和SEM分析了球磨過程中Zr粉的物相組成和形貌演變,采用熱重(TG)法評估了Zr粉的氧化性能。結(jié)果表明:添加CNTs輔助球磨對Zr粉的物相組成沒有影響,但是會影響Zr粉的形貌和氧化性能。不添加CNTs時,隨著球磨時間的增加(1~3 h),Zr粉粒徑持續(xù)減小,球磨3 h后,Zr粉粒徑由十幾微米減小到2~3μm。添加CNTs輔助球磨后,Zr粉的顆粒細(xì)化過程滯后,球磨初期(1~2 h),Zr粉粒徑?jīng)]有顯著變化,直到球磨時間延長到3h時,Zr粉粒徑才開始明顯減小。這是因為CNTs在Zr顆粒表面的黏附和CNTs在Zr粉中的團聚阻礙了磨球?qū)r顆粒的機械沖擊和破碎作用。與直接球磨Zr粉相比,當(dāng)所得Zr粉粒徑相差不大時,添加CNTs輔助球磨使Zr粉的起始氧化溫度和峰值氧化溫度降低了11~37℃,這是因為CNTs的良好導(dǎo)熱性促進了Zr粉氧化過程中的傳熱。另一方面,球磨時間少于2 h時,Zr/CNTs混合物中Zr粉的氧化增重量比純Zr粉的增重量略有降低,但球磨時間超過2 h時,這種趨勢出現(xiàn)反轉(zhuǎn)。前者是因為短時間球磨時,CNTs引起Zr粉的局部團聚,阻礙了團聚體中Zr粉與氧氣的接觸,并且混合物中的Zr粉顆粒還沒有被明顯細(xì)化,這都降低了Zr粉的氧化程度;隨后的反轉(zhuǎn)趨勢是因為球磨時間增加后,混合物中的Zr粉開始明顯細(xì)化,促進了其氧化反應(yīng)的進行,但是純Zr粉由于顆粒尺寸提前細(xì)化而發(fā)生了顯著的自發(fā)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，

本文編號：1956636