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

为了实现欧洲在《Flightpath 2050》中提出的航空愿景，航空业必须大幅减少对环境有害的气体排放，如二氧化碳和氮氧化物。通过提高涡轮机入口温度（泰特）可以显著提高燃气涡轮机的效率并减少排放。目前，发动机最热部分的涡轮机叶片由镍基高温合金制成。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的能力的新型金属超高温材料。难熔金属间化合物复合材料，例如铌硅化物基合金，可以满足工业设定的性能目标。这些合金具有优异的高温强度和抗蠕变性。然而，它们需要环保涂层来提高抗氧化性。涂层将采用粘结层/热生长氧化物/顶层设计。在该项目中，您将利用罗伊斯研究所的世界一流设施，采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）。该材料系统将包括具有平衡性能的铌硅化物基基底和由耐火高熵合金组成的粘合涂层。微观结构，机械和环境性能将被表征，并将模拟基体/粘结层界面的氧化和性能。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.