New materials and manufacturing technologies are essential prerequisites for the development of new ultra-efficient, low-emission engines and thus for the future of aviation.
In the 3DCeraTurb project, the DLR's capabilities in the areas of new materials, design capability, component production, as well as testing and evaluation expertise are bundled and further developed using as demonstrator the development and production of a turbine nozzle guide vane made from two of the most important new material classes, namely additively manufactured (AM) metals and ceramic matrix composite materials (CMC) made of SiC /SiC.
Goals:
The main goals include establishing a process chain consisting of design, manufacturing, coating, validation in a wind tunnel and damage assessment of CMC components. In addition, the development of design and interpretation capabilities and a manufacturing strategy for additively manufactured turbine blades with coatings and AM-compliant cooling structures, including evaluation, will be promoted.
Process:
At the Institute of Materials Research, coating systems developed so far for SiC-SiC CMCs and SLM-manufactured Ni-based alloys are optimized and transferred to the vanes. This includes the characterization of the component surfaces, which is used to derive and develop the necessary smoothing processes with subsequent surface pretreatment, and the coating using PVD processes such as EB-PVD and magnetron sputtering. After coating deposition, the components must be subjected to suitable annealing treatments for crystallization and phase formation in order to achieve the desired coating properties. A focus of the microstructural investigations is the determination of the influence of the blade geometry on the uniformity of the layer thickness along the blade contour and its influence on the layer microstructure and adhesion.
The service life of the different material systems is determined in various tests on additional flat samples. This includes the investigation of degradation mechanisms of the multi-layer systems in the TEGRA temperature gradient test rig, in the thermal cycling test rig (FCT) and in a high-temperature furnace under a steam atmosphere.
