Next-generation materials for turbine engines: Environmental and mechanical performance of a metallic ultra-high temperature materials system

为了满足欧洲在2050年飞行路径中提出的航空愿景，航空业必须大幅减少对环境有害气体的排放，如二氧化碳和一氧化氮。通过提高涡轮入口温度（TET），可以显著提高燃气涡轮发动机的效率并减少排放。目前，发动机最热部分的涡轮叶片是由镍基高温合金制成的。然而，这些材料的表面温度正在接近其熔化温度，因此需要具有超越镍基高温合金性能的新型金属超高温材料。难熔金属间化合物复合材料，如铌硅基合金，可以满足工业规定的性能指标。这些合金具有优异的高温强度和抗蠕变性能。然而，它们需要环保涂层来增强抗氧化性。涂层将采用粘结层/热生长氧化物/面涂层设计。在这个项目中，您将使用先进的粉末冶金工艺（例如场辅助烧结技术/火花等离子烧结（FAST/SPS）或热等静压（HIP））开发材料系统（基材和涂层），利用罗伊斯研究所的世界一流设施。该材料系统将包括具有平衡性能的铌硅化基板和由难熔高熵合金组成的粘结层。微观结构、机械和环境性能将被表征，基材/粘结涂层界面的氧化和性能将被建模。这项工作将加速这些新材料在航空发动机中的应用，提高航空工业的能源效率并减少排放。

In order to meet Europe's vision for aviation, set out in Flightpath 2050, the aviation industry must significantly reduce emissions of environmentally harmful gases, such as CO 2 and NO x . The efficiency of a gas turbine engines can be significantly improved and emissions reduced by increasing the turbine entry temperature (TET).Currently, turbine blades in the hottest part of the engine are made from Nickel-based superalloys. However, surface temperatures of these materials are approaching their melting temperatures, so new metallic ultra-high temperature materials with capabilities beyond Nickel-based superalloys are needed. Refractory metal intermetallic composites, such as Niobium-silicide based alloys, can meet property targets set by industry. These alloys have excellent high temperature strength and creep resistance. However, they will require environmental coatings to boost oxidation resistance. The coating will be of the bond coat/thermally grown oxide/top coat design.In this project, you will develop a materials system (substrate and coating(s)) using advanced powder metallurgy processes (e.g. Field-assisted sintering technology/Spark plasma sintering (FAST/SPS) or Hot isostatic pressing (HIP)) utilising the world class facilities within the Royce Institute. The materials system will comprise of a Niobium-silicide based substrate with a balance of properties and a bond coat comprising of refractory high entropy alloy(s). Microstructure, mechanical and environmental properties will be characterised and the oxidation and properties of the substrate/bond-coat interface will be modelled. This work will accelerate the application of these new materials in aero engines, driving energy efficiency and reducing emissions within the aviation industry.