Oxidation behavior of SiBC matrix modified C/SiC composites with different PyC interphase thicknesses

摘要: Abstract A series of SiBC matrix modified C/SiC composites (C/SiC–SiBC) with different pyrolytic carbon (PyC) interphase thicknesses (50–300 nm) were fabricated by a joint process chemical vapor infiltration, slurry infiltration and liquid silicon infiltration. Oxidation behavior C/SiC–SiBC PyC in the temperature range 800–1200 °C was studied. When exposed at 800 °C for 10 h oxidation kinetics controlled diffusion rate oxygen through micro-cracks coating defects, effect thickness on weight loss apparent. At higher temperatures (>1000 °C) in-depth slowed down due to healing borosilicate glass, defects. Weight all greatly reduced less affected thickness. The flexural strength rapidly decreased after oxidization although thicker brought little improvement it rose up as increased above 1000 °C non-uniform degradation fibers.