Effect of SiC nanowires on ablation property of Cu-doped C/C-ZrC composites.

In-situ SiC nanowires were prepared by sol-gel method, followed by the fabrication of C/C-ZrC composites using low-temperature reaction melt infiltration using Zr-Cu alloy. Thermal physical test results verify that the growth of in-situ SiC nanowires can improve thermal conductivity and minimize interlayer thermal expansion of composites. Addition of SiC nanowires can effectively reduce surface temperature and ablation rates. Thermodynamic calculations revealed the ablative process in the Zr, Si and Cu ternary system, yielding SiO 2 and ZrO 2 as oxidation products. The presence of Si promotes the formation of ZrO 2 oxide layer, while Cu evaporates directly in center region. • C/C-UHTCs prepared by mixing method using Zr-Cu alloy can reduce reaction temperature and maintain the material properties. • The introduction of SiC nw can substantially improve the thermophysical properties of composites prepared by RMI. • Through thermal calculation, ablation protection mechanism of doping Cu and in-situ SiC nw is obtained. [ABSTRACT FROM AUTHOR]