Ag-Al-O体系中纳米Ag形成过程研究

Precipitating Process of Nano-Silver in Ag-Al-O Alloy

摘要:

为了研究Al-Ag固溶体在氧化气氛下热处理过程中Ag的扩散行为与转变过程，采用雾化与高能球磨相结合的方法制备合金粉末，氧化反应合成制备Ag/Al2O3复合材料，通过BSE、XRD、分子动力学的方法，对形成过程的物相变化进行研究。结果表明： Al-Ag固溶体在600 K能够实现较高的单质Ag的析出量，析出的Ag能够控制在纳米尺度内，析出过程伴随着Al2O3致密氧化膜的形成以及内部合金相的转变，计算模型合理地解释和预测了实验结果

Abstract:

In order to investigate the diffusion and transition mechanism of Ag in Ag-Al supersaturated solid during heat treatment in oxidizing atmosphere, Ag/Al alloy powder was prepared by atomization, then Ag/Al2O3 composite was prepared by high energy ball milling and oxidizing reaction. The diffusion rate and the phase state were calculated by the Molecular Dynamics Simulation model of solid solution alloy. The results show that the precipitation of great quantity of Ag occurs at 600 K, accompanied by the formation of compact alumina film and the transition of alloy phase internal particles. The precipitated phase can be controlled in the range of nano size. The experimental results can be explained and predicted properly by the calculated model.