Al-Zn-Mg-(Cu)合金腐蚀与强化相微结构的关系研究

项目名称： Al-Zn-Mg-(Cu)合金腐蚀与强化相微结构的关系研究

项目编号： No.51471067

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 陈江华

作者单位： 湖南大学

项目金额： 84万元

中文摘要： 全世界每年因金属腐蚀造成的直接经济损失约达7000亿美元，我国因金属腐蚀造成的损失占国民生产总值的4%。在我国，以铝合金为主要结构材料的高速列车和大飞机正在飞速发展，铝合金腐蚀是无法避免的问题。腐蚀是材料与复杂环境相互作用的结果，往往从非常微小的区域开始，腐蚀过程中发生的物理化学反应被腐蚀产物严重掩盖，很难被深入认识。近年来，随着电镜技术的发展，人们对材料微观结构的研究更加深入，一些先进的电镜技术也逐渐被引入腐蚀的研究中。本项目拟利用传统的电子显微学技术、原子成像技术、（准）原位技术及三维成像技术等先进表征手段，研究Al-Zn-Mg-(Cu)合金在特定的环境条件下（腐蚀气氛、应力作用）微结构（粗大第二相、纳米析出相、晶界析出相、晶界无析出带、晶粒及晶间结构等）与腐蚀的内在联系。我们的一些前期工作表明在深入理解合金腐蚀微观机理的基础上，优化合金成分及热处理工艺，可以提高合金的耐腐蚀性能。

中文关键词： 铝合金；微观结构；析出相；微合金化；力学性能

英文摘要： It has been estimated that, worldwide, the direct financial loss caused by corrosion reached about $700 billion per year. In China it accounts for 4% of the total gross production of the country. Due to the rapid development of the large aircraft project and high-speed train railway project, corrosion of aluminum alloys that are widely used in transportation vehicles has become a more and more serious issue for scientists and engineers. Inevitably, the study of corrosion resistance ofaluminum alloys shall be promoted and enhanced. The corrosion behaviors of alloys are complex, including self-corrosion and corrosive reaction between the materials and the environment. Hided in corrosion products, and initially occurred in a very small area, the origins of these corrosive reactions are difficult to be directly observed, and therefore difficult to be understood in depth. Recently, it has been demonstrated that electron microscopy can play an important role in gaining in-depth understanding of corrosion mechanism of materials. This proposal aims to investigate the relations between the corrosion behaviors and the precipitates microstructures of the 7XXX Al-Zn-Mg-(Cu) alloys in simulated in-service conditions, such as corrosion environment and loaded stress. the precipitate microstructures consist of the secondary phase particles, hardening nanoprecipitates, grain boundary precipitates, precipitates free zones, and so on. Our prior investgations indicate that understanding the microscopic corrosion mechanism may help to optimize the compositions and the heat treatments to enhance the corrosion resistance of the Al-Zn-Mg-(Cu) alloys.

英文关键词： Aluminum alloy;Microstructure;Precipitates;Micro-alloying;Mechanical properties