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二氧化碳和NOx等环境有害气体的排放。提高涡轮进气温度可以显著提高燃气轮机的效率，降低排放。目前，发动机最热部位的涡轮叶片都是用镍基高温合金制造的。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的金属超高温材料。难熔金属间化合物复合材料，如Nb-硅化物基合金，可以达到工业设定的性能指标。这些合金具有优异的高温强度和抗蠕变性能。然而，它们将需要环保涂层来提高抗氧化性。在这个项目中，您将利用罗伊斯研究所内的世界级设施，利用先进的粉末冶金工艺(例如，现场辅助烧结技术/放电等离子烧结(FAST/SPS)或热等静压(HIP))开发材料系统(基材和涂层(S))。该材料系统将由具有平衡性能的硅化铌基片和由耐火高熵合金(S)组成的粘结层组成。将对微观结构、机械和环境性能进行表征，并对基材/粘结-涂层界面的氧化和性能进行建模。这项工作将加快这些新材料在航空发动机中的应用，提高航空行业的能效和减少排放。

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.