Ce_(80)Cu_(20)合金熔体中原子自扩散与互扩散  

The self-diffusion and inter-diffusion in liquid Ce_(80)Cu_(20)

作　　者：宛波[1] 胡金亮[1] 钟浪祥 张博[1] 

机构地区：[1]合肥工业大学材料科学与工程学院

出　　处：《中国科学：物理学、力学、天文学》2015年第5期76-81,共6页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(批准号:51322103;51171055);全国百篇优秀博士论文作者资助项目(编号:201149)

摘　　要：扩散系数是描述液态金属动力学性质的关键物理量,也是金属材料设计与成型的必要参数.本文利用滑动剪切技术和中子散射技术分别测量了Ce80Cu20合金熔体互扩散系数和Cu原子的自扩散系数,两种扩散系数随温度的变化在所研究的温度范围均符合经典的Arrhenius关系.互扩散系数激活能与Cu原子自扩散系数激活能非常接近,互扩散系数绝对值大约是Cu自扩散系数的1.5倍.根据吉布斯自由能数据,本文还计算了该合金熔体互扩散的热力学驱动力(即热力学因子).结合计算的热力学因子以及经典的描述自扩散和互扩散关系的Darken方程,本文讨论了Ce80Cu20合金熔体中自扩散系数和互扩散系数之间的关系.The diffusion coefficient is not only a key parameter of liquid metal but also important to material design and forming. In this paper, the temperature dependent inter-diffusion coefficients in CesoCu20 liquid metal are measured by the sliding cell method and self-diffusion coefficients are measured by neutron scattering technique. Both these two diffusion coefficients are well fitted by Arrhenius equation and the activation energy of inter-diffusion is close to that of the self-diffusion of Cu atom. It is found that the inter-diffusion coefficients are about 1.5 times larger than self-diffusion coefficients of copper atom. According to the data of Gibbs free energy, we calculate the thermal dynamic driving force （i.e. the thermal dynamic factor） for inter-diffusion of this alloy. The relation between self- diffusion and inter-diffusion in the present liquid alloy is discussed within the framework of Darken equation, which is usually used to describe the relation between self-diffusion and inter-diffusion in the solid crystalline alloy.

关 键 词：Ce-Cu合金熔体 自扩散系数 互扩散系数 滑动剪切技术 中子散射技术 热力学因子 

分 类 号：TG111.6[金属学及工艺—物理冶金]