Aerospace, Vol. 12, Pages 600: Manufacturing Process of Stealth Unmanned Aerial Vehicle Exhaust Nozzles Based on Carbon Fiber-Reinforced Silicon Carbide Matrix Composites

Aerospace doi: 10.3390/aerospace12070600

Authors:
Byeong-Joo Kim
Jae Won Kim
Man Young Lee
Jong Kyoo Park
Nam Choon Cho
Cheul Woo Baek

This study presents the development of a manufacturing process for a double-serpentine (DS) exhaust nozzle for unmanned aerial vehicles (UAVs) based on carbon fiber-reinforced silicon carbide matrix composites (C/SiCs). The DS nozzle is designed to reduce infrared emissions from hot exhaust plumes, a critical factor in enhancing stealth performance during UAV operations. The proposed nozzle structure was fabricated using a multilayer configuration consisting of an inner C/SiC layer for thermal and oxidation resistance, a silica–phenolic insulation layer to suppress heat transfer, and an outer carbon fiber-reinforced polymer matrix composite (CFRPMC) for mechanical reinforcement. The C/SiC layer was produced by liquid silicon infiltration, preceded by pyrolysis and densification of a phenolic-based CFRPMC preform. The final nozzle was assembled through precision machining and bonding of segmented components, followed by lamination of the insulation and outer layers. Mechanical and thermal property tests confirmed the structural integrity and performance under high-temperature conditions. Additionally, oxidation and ablation tests demonstrated the excellent durability of the developed C/SiC. The results indicate that the developed process is suitable for producing large-scale, complex-shaped, high-temperature composite structures for stealth UAV applications.

Source link

Byeong-Joo Kim www.mdpi.com