Design, manufacture and testing of an alloxide fiber reinforced fan blade

Kurzfassung

Alloxide fiber reinforced composites are well known for their damage tolerant behavior up to temperatures of 1000°C. These properties make them attractive for various industrial applications, not only under extreme conditions but also at moderate temperatures when the overall properties are beneficial. One example is a hot gas rotor which will be used in rough industrial processes especially with gas temperature of also far above 600 °C and which must withstand temperature and erosion under long term conditions. In this framework a fan blade prototype was designed, manufactured, tested and evaluated via finite element analysis. First, prepregs are developed from oxide ceramic slurries and oxide fibers. These prepregs enable series production as they can be produced in a reproducible quality and can be stored until being used for manufacturing of components. In order to achieve the mechanical properties of the basic material test coupons were made via stacking of the prepregs and final sintering. With these input data a blade prototype including blade root was designed considering application relevant loads as rotation and aerodynamic resistance. The resulting design was optimized via finite element analysis including the anisotropic layered structure of the alloxide composites. As result a simple wedge design with a complex prepreg lay-up was chosen for a form fit of the blade root in a metallic collar. The fan blade was then produced from the prepregs and sintered in a one piece design. The mechanical proof test of the blade root fixation design was performed in a high velocity centrifuge up to failure. The results were evaluated and compared with the finite element prediction.