Oxidation and recession of plain weave carbon fiber reinforced ZrB2-SiC-ZrC in oxygen–hydrogen torch environment

Abstract

The oxidation and recession of four plain weave carbon fiber reinforced ZrB2-SiC-ZrC composites with different matrix compositions were compared with those of a plain weave carbon fiber reinforced ZrB2-SiC matrix composite. These composites were fabricated using a silicon melt infiltration method. The composite with the higher ZrC content also formed ZrSi2 in the matrix instead of residual silicon. The composites were oxidized at 1700 and 1800 °C in an oxygen–hydrogen torch environment. The oxides consisted of ZrO2 and SiO2, which formed on the surface of all samples. Carbon fiber at the surface was lost due to oxidation. The recession resistance of ZrB2-SiC-ZrC matrix composites remained constant at 1700 °C, even if the matrix composition varied, while the resistance at 1800 °C increased with the matrix of ZrC and ZrSi2. The ZrB2-SiC-ZrC matrix composite with the higher ZrC and ZrSi2 compositions formed a sintered ZrO2-rich layer, which was denser than the ZrO2-SiO2 and improved the recession resistance.