Impact of impurity elements on the corrosion performance of high strength 6xxx aluminium alloys

杂质元素对高强6xxx铝合金腐蚀性能的影响

• 批准号: 2906344
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2906344
• 关键词: Impact; impurity; elements; corrosion; performance

High strength and high crush resistant AA6xxx AlMgSiCu aluminium alloys are presently the preferred choice for applications in the automotive industry for lightweight vehicle structures, including the body-in-white and for the light-weighting and the electrification of both on- and off-road vehicles. However, the increasing global demand for aluminium alloys will only be met in the near term by the circulation of secondary metals, which inevitably introduces impurities to alloys. Increased additions of impurities like iron or deliberate additions like copper and nickel can be detrimental to corrosion resistance particularly in the accelerated tests used for qualification with automotive OEMs. This means that there is a strong research incentive to improve the corrosion performance of wrought AA6xxx automotive alloys in response to this demand and to formulate these alloys from end-of-life recycled aluminium to reduce embedded carbon level to below 2 tonnes CO2e/tonne of aluminium as a supplied component and eventually to Net Zero carbon. Understanding of the role of surface microstructure is critical for the understanding and control of the corrosion performance of extruded AA6xxx alloys in automotive applications particularly for alloys formulated from end of life scrap with higher levels of impurities compared to those formulated from prime aluminium.The objective of the PhD project is to study the surface microstructure of the HSA6 family of high- performance automotive alloys formulated both with deliberate impurity additions and from end-of-life scrap sources like vehicle hulks and from the demolition of buildings. The work will be focused on the influence of alloy microstructure, including die lines and other surface features, constituent intermetallic particles and grain boundary precipitates, on the initiation and propagation of corrosion using correlative accelerated laboratory testing, electrochemical analysis, in situ optical microscopy supported by analytical electron microscopy. The newly developed X-ray and electron-based nanotomography will also be employed to spatially determine the microstructural features that are responsible for the initiation and propagation of corrosion.

高强度和高压抗性的AA6XXX ALMGSICU铝合金目前是汽车行业中适用于轻质车辆结构的应用的首选选择，包括白色的车身以及轻巧和越野车的电气化。但是，只有通过二级金属的循环，全球对铝合金的需求不断增长，这不可避免地会给合金带来杂质。增加杂质（例如铜和镍等故意添加）的杂质增加可能对耐腐蚀性有害，尤其是在用于使用汽车OEM资格的加速测试中。这意味着有很大的研究激励措施可以响应这种需求，以提高锻造AA6XXX汽车合金的腐蚀性能，并从寿命末期回收铝中配制这些合金，以将嵌入式碳含量降低至2吨以下的铝含量低于2吨的铝含量，最终是含铝的组件和净Zero carbone。了解表面微观结构的作用对于理解和控制挤出的AA6XXX合金在汽车应用中的腐蚀性能至关重要加法以及从寿命末的废料来源（例如车辆绿巨人）和拆除建筑物的拆除。这项工作将集中在合金微观结构的影响上，包括模具线和其他表面特征，金属间颗粒和晶界沉淀，对使用相关实验室测试，电化学分析，在分析电子显微镜下支持的情光显微镜使用相关实验室测试，电化学分析的腐蚀引发和传播。新开发的基于X射线和电子的纳米学也将用于空间确定负责腐蚀引发和传播的微观结构特征。