机械合金化法制备Ni-Nb纳米级非晶合金

Preparation of Ni--Nb Base Nano--Amorphous Alloy by Mechanical Alloying

本文采用机械合金化法（MA），以元素粉末为原料，对成分为Ni60 Nb40 的混合粉末进行球磨，采取湿磨和逐步提高球磨速度的方法，制备纳米级非晶合金。利用X射线衍射技术对球磨产物进行物相分析。结果表明，采取湿磨和分步提高球磨速度手段会促进纳米级非晶态组织的形成。此非晶合金的形成是晶粒细化、球磨过程中粒子的表面能增大、缺陷和应力增强等多种作用的结果。

In this paper, pure raw materials of Ni and Nb powder is used to synthesize nano--scale amorphous Ni--Nb base alloy with the desired composition Ni60 Nb40 （at. %） by mechanical alloying. During preparation process, wet milling and step--wise increased milling rate ways are employed deliberately. The microstructural evolution during milling process was characterized by X--ray diffraction. The experimental results show that the wet milling and step--wise increased milling rate ways can promote the formation of nanoscale amorphous structure. The amorphization of Ni--Nb base alloy is thought to stem from several reasons, including refinement of grains, as well as the increase of surface energy, defects, stress of the resultant grains during milling process