固相Ni在液相Zn中的溶解机制

来源期刊：中国有色金属学报2006年第2期

论文作者：孔纲 卢锦堂 许乔瑜

文章页码：268 - 272

关键词：固相Ni； 液相Zn；溶解； 扩散

Key words：solid nickel; liquid zinc; dissolution; diffusion

摘    要：通过研究固相Ni在静止的液相Zn中的溶解行为，建立了自然对流下的溶解速率模型， 确定了不同温度下Ni在液相Zn中的溶解控制步骤。结果表明： 450 ℃时固相Ni在液相Zn中的溶解由界面反应及溶质原子在合金相层中的扩散等因素控制； 550 ℃和650 ℃时, 溶质Ni原子通过液相Zn中浓度边界层的扩散为溶解的主要控制机制； 650 ℃时，γ相从合金层中剥离加速了Ni在液相Zn中的溶解。

Abstract: The dissolution behavior of solid nickel in static liquid zinc was studied and a natural convection model considering intermetallic compound layers formation was established to determine the rate-determining step of dissolution rate of solid nickel in liquid zinc. The results show that the dissolution process is governed by a mixed control mechanism involving diffusion of nickel atom in Ni-Zn alloy layers and the chemical reaction between solid nickel and liquid zinc at 450 ℃. At above 550 ℃, the dissolution rates are controlled by diffusion of nickel atom across a concentration boundary layer in liquid zinc, and the dissolution process seems to be accelerated as γ phase peeled off at 650 ℃.