Due to its excellent mechanical properties, favorable damage tolerance and comparatively low density, continuous carbon fiber reinforced carbon silicon carbide (C/C-SiC) composite fabricated by Liquid Silicon Infiltration (LSI) process has been successfully used in aerospace, energy, and transport technology. [1][2][3][4][5][6][7][8] The preliminary investigation of siliconization in German Aerospace Center Stuttgart started in the late 1980s and the manufacturing process of LSI-based C/C-SiC was developed in the beginning of 2000s. 9 Since then, material properties of the composite have been characterized intensively. The in-plane and out-of-plane mechanical properties under different loads, thermal properties and the effect of high temperature were investigated and summarized in Ref. [10] The strength ratio between bending and tensile load was approx. 1.7-2.0 depending on the different loading directions. 11 The acoustic emission (AE) technique has been used for the determining the relationship between its tensile strength and damage-related AE energy. 12 Based on the statistical analysis, strength values under tensile, compression and bending loads can be described using normal or Weibull

The paper presents manufacture of C/C-SiC composite materials by wet filament winding of C-fibres with a water based phenolic resin with subsequent curing via autoclave as well as pyrolysis and liquid silicon infiltration (LSI). Almost dense C/C-SiC composite materials with different winding angles ranging from ±15° to ±75° could be obtained with porosities lower than 3% and densities in the range of 2 g/cm³. Thermomechanical characterization via tensile testing at room temperature and at 1300 °C revealed higher tensile strength at elevated temperature than at room temperature. Thus, C/C-SiC material obtained by wet filament winding and LSIprocessing has excellent high temperature strength for high temperature applications.Crack patterns during pyrolysis, microstructure after siliconisation and tensile strength strongly depend on the fibre/matrix interface strength and winding angle. Moreover, calculation tools for composites, such as classical laminate and inverse laminate theory can be applied for structural evaluation and prediction of mechanical performance of C/C-SiC structures.

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Oxide ceramic matrix composites (O-CMCs) have a high potential for usage in thermal protection systems or combustion chambers because of their low weight, temperature-and corrosion stability as well as non-brittle failure behavior. Mechanical property changes over their lifetime due to operational loads are not well understood. Moreover, mechanical properties from planar samples under laboratory conditions often differ substantially from upscaled components with complex geometries. In this work, the influences of curvature and preloading conditions were investigated experimentally using modeling to determine boundary conditions. Effects of curvature and trends among preload conditions were determined, with high-cycle-fatigue-preload (HCF) reducing strength and Young's Modulus by 15% compared to their original values where low-cycle-fatigue-preload (LCF) had smaller effect. The low impacts of high temperatures and small-to-medium loads on the properties of O-CMCs makes them an interesting choice for high-temperature combustive environments.