Effects of space extreme temperature cycling on carbon/carbon-(Zr-Si-B-C-O) composites performances

Microstructures, mechanical properties, and oxidation resistance of ZrC-SiC-ZrB₂-ZrO₂ modified carbon/carbon composites (C/C-(Zr-Si-B-C-O)) have been investigated in the simulated space environment with different extreme-temperature thermal cycling (ETC) treatment. Cyclic thermal loading was performed in the temperature range between −120 °C and 120 °C for up to 200 cycles. Results showed that the microstructure degradation of the composite after ETC treatment was attributed to the formation of microcracks and the interfacial debonding. ETC treatment resulted in a 16.98% flexural strength decrease after 200 cycles. An oxidation model on the microstructure evolution of ETC treated C/C-(Zr-Si-B-C-O) composites was proposed to explain the oxidation failure mechanism.