严酷海洋大气环境中冷轧板在非稳态薄液膜下的腐蚀行为与机理研究

项目名称： 严酷海洋大气环境中冷轧板在非稳态薄液膜下的腐蚀行为与机理研究

项目编号： No.U1560104

项目类型： 联合基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 卢琳

作者单位： 北京科技大学

项目金额： 56万元

中文摘要： 冷轧板在海洋大气环境中发生表面腐蚀破坏的本质是非稳态薄液膜下的腐蚀电化学过程。有别于传统的金属/薄液膜体系，生产和储运过程中冷轧板表面形成了由冷轧板/油脂/薄液膜/湿大气组成的多界面体系，这使腐蚀介质（O2，Cl-等）的传质过程及作用机制更加复杂，因此需要对非稳态薄液膜下冷轧板腐蚀过程进行重新认识。本项目利用毛细管微电极和SKP研究了环境影响因素、非稳态薄液膜形成和膜下腐蚀电化学行为三者之间的关系，揭示了模拟海洋大气环境中冷轧板表面的腐蚀电化学行为规律，探明引起腐蚀的临界条件。运用多因素耦合非稳态薄液膜微区电化学装置探明油膜对冷轧板腐蚀过程的影响机制，获得腐蚀性介质在多界面体系中发生扩散的动力学规律。将扫描开尔文力显微镜与Raman光谱相结合，对冷轧板表面形貌、表面电化学状态及腐蚀产物成分的变化过程进行原位动态监测，揭示严酷海洋大气环境中冷轧板在非稳态薄液膜下发生腐蚀破坏的规律与机理。

中文关键词： 冷轧板；海洋大气腐蚀；非稳态薄液膜；微区腐蚀电化学；原位测量

英文摘要： The nature of the corrosive damage occurred at the surface of cold rolled (CR) steel sheet in severe marine atmosphere is a corrosion electrochemical process occurred under unsteady state thin electrolyte film. Differed from traditional metal/thin electrolyte film system, a multi-interface steel/oil film/thin electrolyte film/ wet atmosphere system can be formed on CR sheets during manufacture and warehousing, which complicates the mass transfer processes of such corrosion medium as O2 and Cl- and their mechanism. Thus, it is necessary to renew the understanding for the corrosion process under unsteady thin electrolyte film involved in the CR sheets. In this project, the relationship among environmental factors, the formation of unsteady state thin electrolyte film and the electrochemical behavior are investigated by using the electrochemical microcapillary technique and scanning Kelvin probe (SKP). The marine atmospheric corrosion principle of the CR sheet can be disclosed and the critical condition for the corrosion occurrence can be determined therein. In addition, a setup for measuring the localized electrochemistry under unsteady state thin electrolyte film is employed, in which the environmental factors can be controlled and coupled. With the aid of the setup, the influence of the oil film on the corrosion behavior of the CR sheets can be clarified and the dynamic law for the diffusion process of corrosion medium can be obtained for the multi-interface system. Furthermore, scanning Kelvin probe force microscopy and Raman spectroscopy will be applied to in-situ monitor the dynamic variation of surface morphology, electrochemical state and corrosion products. Therefore the corrosion damage principle and the mechanism of the CR sheets under unsteady state thin electrolyte film will be established especially for severe marine atmospheric environment.

英文关键词： cold rolled steel sheet;marine atmospheric corrosion;unsteady state thin electrolyte film;localized corrosion electrochemistry;in-situ observation