Preparation and Flame Ablation/Oxidation Behavior of ZrB2/SiC Ultra-High Temperature Ceramic Composites
ZrB2/SiC ceramic composites reinforced by nano-SiC whiskers and SiC particles have been prepared by hot-pressing at 1950°C for 1hr under 20 MPa pressure in flow argon atmosphere. Effects of SiC addition on microstructure, mechanical properties and thermal ablation/oxidation behavior of ZrB2/SiC composites were investigated. The results showed that the addition of SiC effectively improved the densification of ZrB2/SiC composites and almost full dense ZrB2/SiC composites were obtained when the amount of SiC increased up to 20 vol%. Flexural strength and fracture toughness of the ZrB2/SiC composites were also enhanced; the maximum strength and toughness reached 600 MPa and 8.81 MPa·m1/2 at SiC additions of 20 vol % and 30 vol%, respectively. The composites possessed good resistance to flame ablation and could keep the whole shape without distinct peeling or cracking after flame ablation by oxyacetylene flame for 3 mins. The more SiC added, the better resistance to flame ablation the composites displayed.
Di Zhang, Jingkun Guo and Chi Y. A. Tsao
C. A. Wang et al., "Preparation and Flame Ablation/Oxidation Behavior of ZrB2/SiC Ultra-High Temperature Ceramic Composites", Key Engineering Materials, Vol. 351, pp. 142-146, 2007