2.1扩散中的不稳定状态ppt课件.ppt
材料科学基础Fundamental of Materials,Prof: Tian Min Bo : 62795426 ,62772851 : tmbmail.tsinghua.eduDepartment of Material Science and EngineeringTsinghua University. Beijing 100084,Lesson twenty-seven,6.4 Non-Steady-State Diffusion ( ),(for one dimensional diffusion only),. Infinite system,1. Formula,2. Discussion: Application: Cx curve. (concentration penetration curve),与时间无关,at x = 0, the concentration is invariable.,Cx curve is symmetrical. ( ),Parabolic grow law,Variation of expression (13),approximation,. Semi-infinite system.,. Thin film. Given:,. Finite system,Examples and Discussions,Exercise,Thank you !,27,