涡流电迁移加速金属表面合金化研究

项目名称： 涡流电迁移加速金属表面合金化研究

项目编号： No.51301185

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 沈明礼

作者单位： 中国科学院金属研究所

项目金额： 25万元

中文摘要： 超超临界火力发电可提高热效率、降低煤耗和CO2排放，是洁净燃煤发电技术的主要方向。锅炉耐热钢管道超临界水蒸汽氧化问题制约其可靠性。耐热钢表面合金化一定含量的Al以达到Al2O3膜形成能力，可显著提升耐热钢的抗水蒸汽氧化性能。传统热扩散渗铝方法的固有缺点难以在诸如锅炉管道等大型构件上实施。本研究将涡流电迁移引入料浆渗铝过程以探索快速高效的新型金属表面合金化方法。本项目拟以耐热钢料浆法渗铝为例，深入探讨涡流电迁移对渗铝动力学、渗层组织结构、成分和相组成及演化的影响规律和机制,并探究该渗铝层的力学和抗超临界水蒸气氧化性能。为发展大型构件快速表面合金化新技术提供理论指导。

中文关键词： 超高速渗铝；电迁移；耐热钢；超临界水氧化；锅炉管道

英文摘要： Ultra supercritical steam power plants, which have higher efficiency, lower coal-consumption and CO2-release, are an important target of clean coal technology. The reliability of this technology is limited by the supercritical steam oxidation of the steels for boiler components. To improve the water vapor resistance of those steels, an effective way is to make the steel possess alumina-forming ability by surface aluminizing. However, it is hard to applying traditional aluminizing techniques to large components such as boiler tubes, due to the inherent defects of the traditional aluminizing techniques. In this research, a novel fast surface alloying technique which uses eddy current-induced electromigration to enhance the diffusion kinetics is introduced in the slurry aluminizing process. The effects of eddy current-induced electromigration on the diffusion kinetics, microstructure, chemical and phase composition of the aluminized layer in boiler steel will be studied. Furthermore, the mechanical properties and supercritical steam oxidation-resistance of the aluminized layer will be investigated. This research will provide theoretical basis for the development of the new technique of fast surface alloying for metallic materials, especially for components with large scale.

英文关键词： Ultrafast aluminizing；Electromigration；Heat-resistant steel；Supercritical water oxidation；Boiler tubing