Structure evolution and ablative mechanism of C/C-ZrC-ZrxCuy composites with low porosity fabricated by pressure assisted reactive melt infiltration

C/C-ZrC-ZrxCuy composites were fabricated by pressure assisted reactive melt infiltration (PARMI). The infil-trated matrix contained three different ZrC-ZrxCuy regions due to the gradient distribution of carbon and Cu during PARMI, and the dimensions of ZrC particles decreased sequentially from matrix boundary to inside. During 30 s ablation, heat-absorbing effect of Cu-phase slowed down the increasement of surface temperature. After 60 s ablation, porous ZrO2 skeleton evolved to a protective integrated cover, including expanded large-scale infiltrator and network of curly whiskers. Thus, ablation rates of composites were reduced to -1.7 +/- 0.1 mu m/s and 1.7 +/- 0.1 mg/s, separately.

Automated summary

C/C-ZrC-ZrxCuy composites were fabricated using the PARMI process, yielding a matrix with three different ZrC-ZrxCuy regions and sequentially decreasing ZrC particle sizes. The heat-absorbing effect of the Cu phase slowed down surface temperature increase during 30 seconds of ablation. After 60 seconds of ablation, the porous ZrO2 skeleton transformed into a protective integrated cover, reducing the ablation rates of the composites significantly.