Hot Corrosion of Nickel alloys for aero-engine applications

该项目将有助于了解耐火元素对镍高温合金腐蚀的基本影响。镍高温合金因其在高温下的优异机械性能而被用于航空发动机的涡轮叶片和盘。罗尔斯·罗伊斯公司作为世界领先的航空发动机制造商，对了解服役合金的失效机制有着浓厚的兴趣，以改进它们。当暴露于含硫化合物中时，一些镍基高温合金的失效速度比其他合金快得多，然而，其机制尚不清楚。当合金暴露于腐蚀性气体和熔盐中时，Mo、W、Re、Ru等难熔元素会加速腐蚀速度。为了了解这些元素的影响，需要进行系统的研究，生产具有不同成分的合金，将耐火材料（Mo/W）与形成保护性氧化物的元素（Cr/Al）交换。你的项目将涉及新合金的生产，先进的表征技术，如扫描/透射电子显微镜，原子探针断层扫描和基于同步加速器的技术。它将包括在不同环境下的机械测试和一些热力学模型，以了解失效机制。

The project will help understand the fundamental effect of refractory elements on nickel superalloy corrosion. Nickel superalloys are used in the turbine blades and discs of aero-engines because of their outstanding mechanical properties up to elevated temperatures. Rolls-Royce plc, as a world leading aero-engine manufacturer, has a strong interest in understanding the failure mechanisms of alloys in service, in order to improve them. Some nickel-based superalloys fail substantially faster than others when exposed to sulphur-containing compounds, however, the mechanisms are not well understood. Refractory elements such as Mo, W, Re and Ru can accelerate the rate of corrosion when the alloy is exposed to corrosive gases and molten salts. A systematic study producing alloys with varying compositions that swap refractories (Mo/W) with elements that form protective oxides (Cr/Al) is required to understand the effect of those elements. Your project will involve the production of new alloys, advanced characterisation techniques such as scanning/transmission electron microscopy, atom probe tomography and synchrotron-based techniques. It will involve mechanical testing under different environments and some thermodynamic modelling to understand the failure mechanisms.