Rocket engine nozzle blocks operate under extreme thermal and oxidative loads, requiring materials with high temperature resistance, dimensional stability, and a predictable lifetime without active cooling. This review provides a comparative overview of multimatrix composite materials-including C/C, C/SiC, SiC/SiC, MMC, and polymer-based ablative systems-representing the full spectrum of materials used in non-cooled rocket nozzles. The study highlights the evolutionary continuum from polymeric ablative systems to carbon, ceramic, and metallic matrices, demonstrating how each class extends operational limits in temperature capability, reusability, and structural integrity. Polymer and ablative composites serve as the foundation of thermal protection through controlled ablation and insulation, while carbon- and ceramic-based systems ensure long-term performance at ultra-high temperatures (>1600 °C). MMCs bridge these classes by combining strength, impact toughness, and thermal conductivity in transition zones. Particular attention is given to manufacturing technologies such as PIP, CVI, LPI, RS, powder metallurgy, casting, diffusion bonding, and filament winding, emphasizing their effect on microstructure, porosity, and lifetime. A practical selection matrix linking nozzle zones, mission profiles, and composite types is proposed, outlining trade-offs among performance, mass, lifetime, and manufacturability, and guiding the design of next-generation thermal protection and propulsion systems based on the multimatrix concept.

This article presents the results of research on materials used in the nozzle section of a rocket engine. The study analyzed the properties of high-strength metal alloys, heat-resistant, and thermal insulation materials. A review of materials proposed for use in nozzle constructions was conducted. Three different materials were selected for experimental studies: structural steel 30KhGSA, textolite (grade A), and pressed graphite. To assess the thermal and erosion resistance of these materials, fire tests were conducted on a 70 mm caliber engine test stand. As a result of the tests, the level of erosion wear was determined in different nozzle zones: the converging section, the throat, and the diverging section. Changes in the geometric dimensions (diameter and angles) of nozzle components were monitored. The graphite material demonstrated the highest thermal and erosion resistance in the throat region. While steel materials are effective in terms of mechanical strength, and textolite is suitable as a thermal insulator, it was found to be significantly worn under high temperatures. Overall, the results of the conducted research can serve as a scientific and practical basis for designing and selecting materials for rocket engine nozzle blocks. The work provides recommendations for the proper selection of materials for small- and medium-caliber solid-fuel rocket engines.

Research and production of armor-resistant steel in Kazakhstan.