文献类型：期刊文献

英文题名：Coupling effects of chemical stresses and external mechanical stresses on diffusion

作者：Xuan, Fu-Zhen[1];Shao, Shan-Shan[1];Wang, Zhengdong[1];Tu, Shan-Tung[1]

机构：[1]E China Univ Sci & Technol, MOE Sch Mech Engn, Key Lab Safety Sci Pressurized Syst, Shanghai 200237, Peoples R China

年份：2009

卷号：42

期号：1

外文期刊名：JOURNAL OF PHYSICS D-APPLIED PHYSICS

收录：;EI(收录号：20091512027489);WOS:【SCI-EXPANDED(收录号:WOS:000261761800048)】；

语种：英文

外文关键词：Stresses - Finite difference method - Partial differential equations

摘要：Interaction between diffusion and stress fields has been investigated extensively in the past. However, most of the previous investigations were focused on the effect of chemical stress on diffusion due to the unbalanced mass transport. In this work, the coupling effects of external mechanical stress and chemical stress on diffusion are studied. A self-consistent diffusion equation including the chemical stress and external mechanical stress gradient is developed under the framework of the thermodynamic theory and Fick's law. For a thin plate subjected to unidirectional tensile stress fields, the external stress coupled diffusion equation is solved numerically with the help of the finite difference method for one-side and both-side charging processes. Results show that, for such two types of charging processes, the external stress gradient will accelerate the diffusion process and thus increase the value of concentration while reducing the magnitude of chemical stress when the direction of diffusion is identical to that of the stress gradient ((M) over right arrowM, (D) over right arrow = 1). In contrast, when the direction of diffusion is opposite to that of the stress gradient ((M) over right arrowM, (D) over right arrow = -1), the external stress gradient will obstruct the process of solute penetration by decreasing the value of concentration and increasing the magnitude of chemical stress. For both-side charging process, compared with that without the coupling effect of external stress, an asymmetric distribution of concentration is produced due to the asymmetric mechanical stress field feedback to diffusion.