Characterization and Simulation of Bending Properties of Continuous Fiber Reinforced C/C-SiC Sandwich Structures

Kurzfassung

At the Institute of Structures and Design of German Aerospace Center (DLR) in Stuttgart, C/C-SiC sandwich structures based on continuous fiber reinforced folded cores and skin panels have been developed via Liquid Silicon Infiltration (LSI) and in situ joining method. The resulting lightweight structures offer a high potential in various application areas such as optical benches of satellites or charging racks for high temperature furnaces. A major impediment for the new development and practical application of ceramic sandwich structures is the lack of know-how of characterization and simulation of their mechanical properties. In this study, several types of C/C-SiC sandwich structures with folded cores with different fiber orientations (0°/90° and ±45°) in the core structure were manufactured and mechanically tested in four point bending. The mechanical properties of the different sandwich structures were correlated to analytical calculation and numerical (finite element) simulation. The comparison showed good correlation. The proposed evaluation methods are suitable to determine and simulate the mechanical properties of C/C-SiC sandwich structures and are a versatile tool for further product development.