The influence of ablation products on the ablation resistance of C/C–SiC composites and the growth mechanism of SiO ₂ nanowires

Abstract

Ablation under oxyacetylene torch with heat flux of 4186.8 (10% kW/m2 for 20 s was performed to evaluate the ablation resistance of C/C–SiC composites fabricated by chemical vapor infiltration (CVI) combined with liquid silicon infiltration (LSI) process. The results indicated that C/C–SiC composites present a better ablation resistance than C/C composites without doped SiC. The doped SiC and the ablation products SiO2 derived from it play key roles in ablation process. Bulk quantities of SiO2 nanowires with diameter of 80 nm–150 nm and length of tens microns were observed on the surface of specimens after ablation. The growth mechanism of the SiO2 nanowires was interpreted with a developed vapor–liquid–solid (VLS) driven by the temperature gradient.

Experimental and Numerical Evaluation of the Ablation Process of Carbon/Carbon Composites Using High Velocity Oxygen Fuel System

“…Fiber chippings were clearly observed on the tips of such needle-like shapes. This was the dominant failure mode of perpendicular fiber bundles, which was in agreement with the results reported by Li et al [20].…”

ReaxFF molecular dynamics study on oxidation behavior of 3C-SiC: Polar face effects

“…[1][2][3] However, because of the high-temperature and high-pressure working condition, oxidation occurs which can lead to system degradation. [4][5][6][7] Therefore, the understanding of related behaviors involving chemical reaction and microstructure evolution turns out to be a critical issue.…”

Experimental Investigation of the Anisotropic Thermal Conductivity of C/SiC Composite Thin Slab

“…Continuous fibers are usually introduced as reinforcement to improve the comprehensive performance of polymer and ceramic materials. [1][2][3] Carbon fiber-reinforced SiC matrix (C/SiC) composites combine the benefits of carbon fiber and a SiC matrix, which can be applied in thermal protection fields, such as in supersonic aircraft, rocket engines, nuclear reactors and gas turbines. [4][5][6] There are many SiC matrix composite manufacturing methods, such as liquid silicon infiltration, [7] polymer impregnation pyrolysis, [8] chemical vapor infiltration (CVI), [6] and reactive melt infiltration.…”