Thermomechanical and thermophysical properties of liquid siliconized C/C-SiC

Mechanical properties (strength, stiffness and stress-strain behaviour) and physical properties (thermal expansion and conductivity, heat capacity and emissivity) of C/C-SiC (manufactured at DLR Stuttgart by liquid siliconization process) have been investigated at temperatures up to 1600°C. Sophisticated facilities have been developed and established for the thermomechanical testing of flat and tubular C/C-SiC-specimens under tension, compression and torsion loading (static and dynamic) and also for combined multiaxial loading. A non-linear stress-strain behaviour from the beginning of the load was observed. This nonlinearity is independent of the parameters specimen goemetry, size and temperature. The test results have been correlated with analytical approaches. Thermophysical properties of samples with different types of woven (Atlas, Leinwand, Koper) fibres (Toray T300, Toray M40) and varying volume content of fibres were measured and the results have been used to apply theoretical models available from the literature to calculate the properties of the material components.