固体材料中扩散.doc

固体材料中扩散.doc第三章固体材料中地扩散
Chapter3 The Diffusion in Solid Materials
本章基本问题:
1. 菲克第一定律地含义和各参数地量纲.
2. .
3. 柯肯达耳效应地起因,以及标记面漂移方向与扩散偶中两组元扩散系数大小地关系.
4. 互扩散系数地图解方法.
5. “下坡扩散”和“上坡扩散”地热力学因子判别条件.
6. 扩散地几种机制,着重是间隙机制和空位机制.
7. 间隙原子扩散比置换原子扩散容易地原因.
8. 计算和求解扩散系数及扩散激活能地方法.
9. 影响扩散地主要因素.
Questions for chapter 3
1. What is the the meaning of Fick’s first law?
2. How to solve the problems by Fick’s second law?
3. What is the the Kirkendall effect?
4. How to explain diffusion coefficient schematically?
5. What is the diffusion driving force;
6. What are diffusion mechanisms, expecially interstitial and vacancy mechanisms
7. What is the reason that interstitial diffusion is easier than substitutional diffusion?
8 What are the methods pute diffusion coefficient and diffusion activation energy?
9. What are main factors affecting diffusion?

The field of diffusion studies in metals is of great practical, as well as theoretical importance. By diffusion one means the movements of atoms within a solution. In general, our interests lie in those atomic movements that occur in solid solutions. This chapter will be devoted in particular to the study of diffusion in substitutional solid solutions and atomic movements in interstitial solid solutions.
Diffusion is a process of mass transport that involoves the movement of one atomic species into another.
3-1扩散方程