摘要
基于Fick第二定律、化学动力学及扩散热力学,推导得到了扩散、化学反应等因素耦合作用下的修正Fick 2定律,以薄板为对象,差分求解得到尘化腐蚀过程中不同因素作用下基于两种扩散模型内部瞬时碳浓度分布图,并结合Cr5Mo钢的尘化腐蚀试验,分析了化学反应因素在扩散中作用。研究结果表明:c-Fick 2中修正项系数k～值对计算得到的浓度值有重要的影响;随着k～值的增大,浓度值下降得越多,当k～≤1时对扩散的影响不显著;本试验条件下k～=2.0769,化学反应因素对碳扩散的影响较小,该模型可以描述尘化腐蚀试验过程中的碳浓度分布情况,对尘化腐蚀程度的预测提供了依据。
Based on Fick 2 Law,chemical kinetics and diffusion thermodynamics,the modified Fick 2 Law is obtained under the consideration of the coupling effect of diffusion and chemical reaction.According to dusting corrosion experiment of Cr5Mo steel,the concentration distribution of solute in thin plate under different factors can be obtained by using finite difference method based on two diffusion models in the process of metal dusting.The effect of chemical reaction in diffusion is also analyzed.According to the results of the research,the modified coefficient k~ of c-Fick 2 has a significant effect on the concentration value;With the increase of k~,the concentration value is deceasing.When k~≤1,the value of k~ has not obvious impact on the diffusion.Under the experiment condition of this paper,the value of k~ is 2.0769,and the factor of chemical reaction has slight impact on the diffusion of carbon.This model can be used to depict the distribution of carbon concentration during the dust corrosion experiment process and provide evidence for prediction of metal dusting corrosion.
出处
《压力容器》
北大核心
2011年第7期1-5,34,共6页
Pressure Vessel Technology
基金
国家自然科学基金项目(50675096)
