Advanced ceramic materials and composite systems, including structural ceramics, functional ceramics, fiber-reinforced composites, nanocomposites, and high-temperature materials
6 papersHigh-entropy ceramics (HECs) are a new class of materials with diverse crystal structures and electronic configurations, enabling unique property combinations not found in traditional ceramics. These materials exhibit enhanced hardness, low thermal conductivity, and tunable thermal expansion, showing promise for applications ranging from thermal protection to energy storage and catalysis.
Hot and cold compression techniques were used to create densified silica glass, revealing a transition from low to high-density amorphous structures. This densification leads to changes in network topology, detectable using persistent homology, and influences heat capacity and the boson peak in dynamical spectra, indicating a connection between the nature of structural disorder and material properties.
Silicate glass alteration is a complex process involving ion-exchange, hydrolysis, and gel formation, with different mechanisms dominating depending on the glass composition and environment. While progress has been made in understanding these mechanisms at various scales, developing holistic models that accurately predict long-term behavior remains a challenge, especially for complex systems like nuclear waste glass.
This review examines various sol-gel methods to synthesize porous ultra-high temperature ceramics (UHTCs), including templating, foaming, and solvent evaporation. These methods allow for tailoring of pore size and porosity, offering materials suitable for thermal insulation in extreme environments like hypersonic vehicles, though further research on applications and some material properties is needed.
This review summarizes various nanocomposite materials, their properties, manufacturing methods, and applications in the aerospace industry, emphasizing their potential for lightweight structures, radiation protection, and enhanced mechanical properties. While it covers a wide range of materials and techniques, the review lacks a deep critical analysis and clear future research directions, affecting its overall contribution to the field.
Ultra-high temperature ceramics (UHTCs) are promising materials for hypersonic vehicle applications due to their high melting points and excellent oxidation/ablation resistance. The review covers the processing, properties, and recent advances in UHTCs, composites, and coatings, including the emerging field of high-entropy UHTCs.