Although the incorporation of ultra-high temperature ceramics (UHTCs) significantly enhances the oxidation and ablation resistance of C/C composites, the spatial architecture of carbon fibers also substantially influences composite properties. To clarify the structural effects, needled 2.5D and stitched 3D C/C-ZrC composites were fabricated via precursor infiltration and pyrolysis (PIP). Flexural testing and oxyacetylene ablation evaluation were conducted to assess the impact of carbon fiber architecture on mechanical and ablation-resistant behavior. Finite element analysis (FEA) revealed that the puncture fiber bundles in 3D composites facilitate both load transfer and heat dissipation. These fiber bundles alleviate surface stress concentration, thereby enhancing material strength, while the induced compressive stress preserves oxide scale integrity. These findings demonstrate the effect of spatial architecture on composite performance. Concurrent matrix optimization and structural design are essential for superior property of UHTC-modified C/C composites.

Improving the ablation resistance of carbon/carbon (C/C) composites in high-temperature oxidative environments is critical to the effective design of thermal protection systems in aerospace applications. However, the exploration of the matrix ablation behavior of C/C composites has received limited attention in existing research. In this study, two types of 2.5D needle-punched preforms were designed through structural optimization for C/C composites, using mesophase-pitch-based carbon fiber (CFMP) and polyacrylonitrile-based carbon fiber (CFPAN) as reinforcements, respectively. Subsequently, 2.5D CFMP/C-ZrC-SiC and 2.5D CFPAN/C-ZrC-SiC composites, serving ZrC and SiC as the ablation-resistant ceramic phases, were fabricated via a combined process of chemical vapor infiltration (CVI) and precursor impregnation pyrolysis (PIP). Benefiting from the high thermal conductivity of CFMP, 2.5D CFMP/C-ZrC-SiC composites exhibited a thermal conductivity of 87.30 W/m*K at room temperature. Under high-temperature ablation conditions, its surface temperature was reduced by a maximum of 200 degrees C compared with that of 2.5D CFPAN/C-ZrC-SiC composites. On this basis, a 3D CFMP punctured preform was designed to further explore the effect of the preform structure on the ablation performance. The improvements in thermal conductivity and mechanical properties conferred by the 3D structure further enhanced the ablation resistance of CFMP/C-ZrC-SiC composites. The composite exhibited linear and mass ablation rates of 1.983 mu m/s and 1.776 mg/s, respectively, providing a valuable reference for the design of thermal protection systems for hypersonic vehicles and structural materials used in extreme environments.

To enhance the ablation resistance of ultra-high temperature ceramic (UHTC) coatings on modified C/C composites, doping is often adopted to increase melt viscosity, yet it may simultaneously accelerate oxygen permeation. In this work, a composite oxide (La2ZrxOy-ZrO2) coated ZrC powder was synthesized via a sol-gel method and deposited as a (La2ZrxOy-ZrO2)@ZrC coating onto a SiC-interlayered C/C substrate by supersonic atmospheric plasma spraying. Plasma ablation tests were performed on coated nose-cone-shaped specimens under multiple incidence angles to better simulate realistic spacecraft re-entry conditions. The coating exhibited outstanding ablation resistance, with mass and linear ablation rates as low as 0.083 mg/s and 1.67 mu m/s, respectively. A stable oxygen barrier, composed of monoclinic ZrO2 crystals and molten La2Zr2O7, formed during ablation, effectively impeding oxygen penetration without rare-earth dissolution into the ZrC oxide. This study confirms that a core-shell structured composite oxide coating can provide durable protection for C/C composites under extreme conditions.

(TiZrHfNbTa)C high-entropy ceramic is a category of ultra-refractory materials essential for applications in extreme environments, such as nuclear fusion reactors and aerospace thermal protection systems. Nanosecond lasers provide a new approach for achieving excellent surface integrity and dimensional accuracy. The influence of nanosecond lasers on the material removal mechanism and surface characteristics was systematically investigated through a combination of computational modeling and experimental validation. Equimolar HfC, TaC, ZrC, TiC, and NbC powders were employed as precursors to prepare (TiZrHfNbTa)C high-entropy carbide bulk ceramics by means of 1spark plasma sintering, and as shown here, the resultant ceramics were synthesized through this specific sintering technique. The samples were machined with a nanosecond laser at power levels of 4, 7, 10, and 13 W. The results show that nanosecond laser ablation induces a hierarchical oxidation sequence: Zr and Hf undergo preferential oxidation due to their lower ionization energies, followed by Ti, and finally Nb and Ta. A laser power of 10 W was found to provide a critical balance between manufacturing capability (kerf width = 161 μm and heat-affected region <5 μm) and surface quality. Thermal accumulation progressively intensifies with elevated laser power, culminating in reduced efficiency and compromised surface integrity. This study establishes a foundational framework for the precision manufacturing of refractory high-entropy ceramics, demonstrating that nanosecond lasers can achieve micron-scale precision while minimizing thermal damage. These findings provide valuable guidance for demanding applications in aerospace thermal protection, nuclear reactors, and concentrated solar energy systems.

This study develops a hybrid phase field model that simulates intralaminar and interfacial failures in fiber-reinforced composite materials. To capture the influence of fiber orientation on crack mode within the composite layer, we introduce a coordinate-transformation matrix defined in global and local systems. Using this transformation, we establish a new crack density function and derive the previously employed structural tensor, which clarifies its physical significance. Concurrently, we derive the Hashin failure criteria for the fiber and matrix and construct the damage evolution law within the composite layer. To account for the influence of the interface on composite failure, we propose an interface phase-field model. We construct the interface traction-separation criterion and potential energy function, develop the interface mixed-mode driving force, and derive a quadratic stress failure criterion for interface failure, together with its corresponding damage evolution law. Finally, we propose a hybrid element method to solve the phase field models within the composite layer and interface. This strategy enables the phase field models across the two regions to interact through phase field exchange, rendering the damage field continuous within both the layer and the interface. Ultimately, the proposed model was verified by multiple numerical examples. The numerical results validated the effectiveness of the model and provided a novel approach for failure analysis within and between composite layers.

Resistance to cyclic ablation is critical for thermal protection system of reusable high-speed vehicles. To address the spallation problem of the oxide scale formed on UHTC-modified C/C composites during cyclic ablation, C/C-ZrC-SiC composites with a ZrO2 short-fiber-reinforced oxide scale (CZS-FOS) were fabricated via reaction melt infiltration (RMI). The stability of the oxide scale under high-temperature scouring conditions was evaluated using an oxyacetylene flame with a heat flux of 4.2 MW/m2. Results demonstrate that CZS-FOS exhibits superior cyclic ablation resistance. Microstructural analyses revealed that a "skeleton structure" oxide scale incorporating in-situ-formed ZrO2 short fibers effectively inhibits the crack propagation and oxide scale spallation, thereby protecting the composites from further ablation. By constructing such an oxide-fiber-reinforced oxide scale, this work provides an effective approach to extend the cyclic service life of UHTC-modified C/C composites in extreme environments.

Carbon/carbon (C/C) composites suffer from limited ablation resistance due to oxidation and sublimation under extreme aerodynamic heating. While enhancing thermal conductivity can actively dissipate heat and reduce ablation rates, this often degrades thermomechanical properties. To resolve this trade-off, we propose a fiber lamination hybridization strategy that combines high thermal-conductivity mesophase pitch-based carbon fibers and high load-bearing polyacrylonitrile-based carbon fibers (CFPAN). This approach tailors interlaminar thermal stress, promoting both interlaminar microcrack deflection and stress-induced graphitization degree in the matrix. Consequently, the hybrid composites exhibit simultaneously improved flexural strength (slightly higher than CFPAN-reinforced laminated C/C composites) and in-plane thermal conductivity (up to 430 W m-1 K-1). The synergistic effects significantly enhance ablation resistance by not only reducing ablation-induced heat accumulation via active heat dissipation but also resistance to mechanical exfoliation. These advances enable the hybrid C/C composites to achieve superior comprehensive performance in complex aerodynamic environments. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

It is a common approach to construct material structures using high-aspect-ratio units for specific functionalities. However, the realisation of structural and functional continuity from individual building blocks remains challenging. Inspired by the inosculation of twinned-trunk in nature and the capability of resource sharing and exchange, a new strategy for assembling porous 3D carbon networks is developed in this study. In this design, carbon nanotubes (CNTs) were in-situ grown on carbon fibres (CFs) to initiate nano-branching by chemical vapour deposition, and pyrolytic carbon (PyC) was subsequently deposited on the CNTs and CFs to form an interconnection between adjacent fibres. This inosculation structure, mimicking the cellular fusion between trunks and branches, established continuous interconnections between independent carbon phases. As proof of resource sharing with functional continuity, the inosculated heterogeneous carbon network was incorporated into polydimethylsiloxane matrices after graphitisation for prompting heat conduction. The fabricated composites demonstrated substantially improved thermal conductivity, attaining a through-plane value of 18.8 W/(m K) at 21.4 vol% carbon material loading. This inosculation assembly strategy provides a transformative paradigm for constructing advanced functional materials requiring continuous interconnected 3D networks. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

The 2.5D woven carbon fiber reinforced silicon carbide CMC overcomes the shortcomings of weak interlayer bonding in 2D fabrics and performance degradation caused by yarn buckling in 3D fabrics. By interweaving warp and weft yarns, this method achieves simultaneous improvement in in-plane performance and interlaminar strength, resulting in more stable mechanical properties for CMCs in complex aerospace environments. However, current research on CMC fabrics predominantly focuses on 2D and 3D structures, leaving the constitutive relationship of 2.5D woven Cf/SiC under isotropic stress loads insufficiently studied. To address this gap, this research employed 2.5D shallow orthogonal woven Cf/SiC fabrics (2.5D-SO-Cf/SiC) as the subject and adopted a sequential multiscale approach to establish its constitutive model. In the model establishment process, theoretical analysis, numerical simulation, and experiment testing were integrated to characterize and formulate the elastic response model under diverse mechanical loading conditions. Through theoretical research and finite element calculations, this study established the numerical relationship between the macroscopic material properties of 2.5D-SO-Cf/SiC and the properties of its constituent materials across multiple scales, culminating in a final mesoscale constitutive model. The validity and accuracy of the proposed model were verified via macroscopic experiments on specimens subjected to mechanical loads in multiple directions.

High thermal conductivity carbon/carbon (C/C) composites reinforced with mesophase pitch-based carbon fibers (CFMP) can balance thermal loads, alleviate thermal gradient stresses, and improve ablation resistance in aerothermal protection components. However, their insufficient load-bearing capability remains a key limitation for structural applications. Herein, high-strength polyacrylonitrile-based carbon fibers (CFPAN) were hybridized with highly thermally conductive CFMP to synergistically regulate the mechanical performance and thermal conductivity of C/C composites. The relationships among fiber hybridization, microstructural evolution, flexural behavior, thermal transport, and oxyacetylene ablation resistance were investigated. Low CFPAN incorporation produced a pronounced positive hybrid effect: at ηPAN = 11.11%, the flexural strength reached 399 MPa, representing a 27.1% increase relative to the pure CFMP-reinforced composite. At this low hybrid ratio, the composite maintained a thermal conductivity above 425 W/(m·K), indicating a balance between high thermal conductivity and load-bearing capability. Microstructural analysis revealed that fiber hybridization regulated graphitization of the pyrolytic carbon (PyC) matrix and homogenized the pore and defect size distribution. During oxyacetylene ablation, CFMP provided efficient heat transfer pathways, whereas CFPAN formed a stable load-bearing skeleton against gas erosion. After 60 s of high-heat-flux ablation, the composite with ηPAN = 52.94% exhibited a linear ablation rate approximately 40% lower than that of the pure CFMP-reinforced composite. These findings demonstrate a fiber hybridization route for optimizing thermal transport, mechanical reliability, and ablation resistance in C/C composites.

Carbon–carbon (C/C) composites are ideal materials for thermal protection in hypersonic vehicles but suffer severe oxidation at high temperatures, necessitating the development of high-performance protective coatings. To overcome the limitations of conventional SiC/ZrC alternating coatings, this study employed catalyst-assisted chemical vapor deposition to synthesize ZrC nanowires in situ on C/C composites, optimizing growth by adjusting temperature and catalyst concentration. Subsequently, SiC/ZrC alternating coatings were deposited onto the ZrC nanowires, with pure SiC/ZrC alternating coatings serving as controls. The results identified optimal parameters for uniform ZrC nanowire growth, which remarkably improved the interfacial bonding and mechanical properties of the coated C/C composites compared with the control samples. After 90 s of oxyacetylene ablation and 30 s of plasma ablation, the nanowire-reinforced coatings maintained excellent structural integrity, exhibiting low mass ablation rates of 0.51 and 0.53 mg/s, as well as linear ablation rates of −0.67 and − 0.63 μm/s, respectively. In contrast, the pure coatings experienced structural degradation and imminent failure under the same extreme conditions. Mechanistically, ZrC nanowires play a critical role. They establish efficient multidimensional heat conduction pathways and form a compact oxide layer that reduces thermal damage and oxygen penetration during oxyacetylene ablation. Additionally, the nanowires enhance hardness and interfacial bonding strength and construct an internal stress dissipation network that suppresses frequent crack propagation and coating spalling under plasma ablation. This work provides theoretical and technical support for the development of ultra-high-temperature thermal protection coatings for hypersonic vehicles.

Multifunctional carbon fiber structural batteries simultaneously provide mechanical load-bearing and energy storage capabilities, offering significant potential to replace conventional structural components, thereby enhancing the overall energy density of the system. However, achieving high multifunctional efficiency remains challenging, as lithium-ion transport in carbon fibers is restricted at high current densities, resulting in poor rate capability and significantly decreased reversible capacity. To solve this problem, this work develops an integrated structural anode of carbon/carbon composite (C/C) for both structural support and energy storage. Atomic force microscopy combined with in situ characterization techniques, including in situ Fiber Bragg Grating sensing, in situ electrochemical impedance spectroscopy, and Operando Raman spectroscopy, reveals that the unique "onion-skin" buffering structure in C/C significantly enhances the mechano-electrochemical properties of the electrode through a synergistic "shielding-channeling" mechanism. The all-fiber structural lithium-ion battery with commercial organic electrolyte demonstrates a high energy density of 60 Wh kg-1 with excellent power density (65 W kg-1) and cycling stability. Remarkably, it achieves a record-high near-unity multifunctional efficiency (0.96), while maintaining remarkable electrochemical stability under tensile, bending and out-of-plane compressive conditions, demonstrating great potential for applications in aerospace systems, intelligent transportation, and next-generation lightweight structural energy storage technologies.

The mechanics of structural ceramics, especially the toughness, are crucial to their service reliability and need to be continuously optimized. Inspired by the "brick-mortar" structure and further adjusting the microstructure of "mortar" on the interface, ceramic with strength and toughness up to 444.16 MPa and 13.79 MPa center dot m1/2 is constructed by hot pressed sintering with alumina (Al2O3) as brick and vertical graphene (VG) with active atomic edges as mortar. Relying on the covalent interface between VG grown insitu and Al2O3, the sliding of Al2O3 links the shear-deformation process of the crosslinked and interlocked nanointerface formed by VG, making the VG-enhanced Al2O3 ceramics (AVG) obtain super toughness. Moreover, the structure of interlocked VG-nanointerface exhibits an excellent high-temperature resistance, which makes AVG still show the excellent strength of 437.66 MPa and toughness of 11.16 MPa center dot m1/2 after heat treatment at 1500 degrees C for 100 h and they are respective 2.51 times and 3.18 times higher than Al2O3 in the same condition. This work provides a new thought for the preparation of high-strength, ultra-tough and high-temperature mechanical stable ceramics. (c) 2024 The Authors. Published by Elsevier B.V. on behalf of The Chinese Ceramic Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Isotropic pyrolytic carbon (IPC) is renowned for its robust mechanical, biological, and tribological properties. However, the current mechanisms for modulating IPC microstructure are insufficient to achieve higher performance. Herein, this study provides nanoscale insights into the formation and property regulation of the core-shell structure of the IPC, integrating simulation and experimental approaches. Largescale reactive molecular dynamics simulations elucidate the microstructural evolution and assembly processes from precursors to nanoparticles and intertwined graphene networks. Simulation process characterization enable versatile adjustment of IPC microstructural features and one-step deposition of hybrid structures with disordered cores and ordered shell layers. Compared to Pyrolytic carbon (PyC) with laminated graphene arrangement, the prepared hybrid structure enables rapid assembly of large-size standalone carbon components. Moreover, the hybrid architecture effectively improves the core-shell phase connection and significantly increases the interfacial shear stress within the intertwined graphene shell layers. Consequently, it greatly improves load transfer efficiency and enhances crack-bridging toughening effect. The endeavor to establish precise microstructure formation and property regulation in IPC materials promises to steer high-performance carbon materials toward distinct developmental trajectories. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

The ZrB2-SiC coatings were prepared on SiC-coated 3D C/C composites with different substrates by supersonic atmospheric plasma spraying. Ablation tests of 80 s and 20x4 s were carried out in an oxyacetylene flame with a heat flux of 2.38 MW/m2 to evaluate the ablation resistance and thermal shock resistance of the ZrB2-SiC coating. Results show that the substrate of the HTC-XZZ specimen provides long-distance heat transfer channels, leading to a reduction of 174 degrees C and 237 degrees C in the surface temperature of the coating, which weakens the SiO2 consumption. Combined with the pinning stability of the sawtooth SiC inner layer on oxide film, ZrSiO4 is formed, which improves the compactness of the coating and effectively prevents oxygen diffusion, has good structural stability, and exhibits excellent ablation resistance and thermal shock resistance. This new thermal structure coating shows great application prospects in the field of thermal protection of materials.

The difference in the reactivity of carbon/carbon (C/C) composite constituents leads to complex oxidation morphology, which poses a challenge to the prediction of material decomposition and mechanical property degradation in an oxidizing environment. In this paper, a PD-FEM coupling approach is proposed to analyze the oxidation morphology evolution and through-thickness compressive failure after oxidation of C/C composites. For the oxidation analysis, a peridynamic oxidation model is developed to capture the oxidation interface of C/C composites at microscale and mesoscale. Based on the oxidation morphology, the microcracking-based finite element model is employed to calculate the compression failure. This approach is validated by the oxidation experiments and the experiments of compression after oxidation. Finally, the oxidation mechanism at different scales and the effect of oxidation on the compression failure behavior of C/C composites are investigated.

High-temperature-resistant, high-strength, and lightweight multifunctional aerogels are urgently required for critical thermal management in harsh conditions, but balancing many factors is highly difficult. Zirconium carbide nanowires (ZrCnws) have received increasing attention due to their exceptional high-temperature stability. In this work, ZrCnws aerogels were prepared by freeze-drying and heat treatment methods without metal catalysts. The single ZrCnw shows a cylindrical structure with a smooth surface. The growth of ZrCnws relied on S-L-S mechanism. ZrCnws aerogels have a density of approximately 24.38 mg/cm3 and low thermal conductivity of 33.8 mW/(m center dot K) at room temperature. ZrCnws aerogels have 74.88% height retention after 100 cycles of compression at 30% strain and exhibit a specific EMI SE of 1458.61 dB center dot cm3 center dot g- 1 in the X band. This work provides a feasible method for ZrCnws aerogels and verifies that the prepared ZrCnws aerogels have potential applications in the fields of thermal insulation and electromagnetic shielding.

Carbon nano-materials can strengthen the mechanical properties of C/C composites, but it is difficult to be uniformly introduced into the interior of performs. In this paper, a new strategy of efficiently loading carbon nanofibers (CNFs) by air compression spraying method before preform preparation was proposed, and CNFs were successfully introduced into the interior of the preform, and the CNFs-modified 2.5D C/C composites were prepared with improved mechanical and ablation properties. Results show that the CNFs-modified layer around the fibers increased the interfacial shear strength of the fiber/matrix interface by 57.4%. Coupled with the mechanism of energy dissipation through the pull-out of CNFs, the flexural strength of the CNFs-modified C/C composites increased from 195 MPa to 243 MPa, an increase of 24.6%. CNFs provided a large number of nucleation sites for the deposition of pyrolytic carbon, enhanced the cohesion of the matrix, and promoted the release of thermal stress during the heat treatment at 2450 degrees C. As a result, the CNFs-modified C/C composites exhibited high thermal stability and the strength retention rate of up to 77%. In addition, CNFs reduced the interfacial thermal resistance between the fibers and the matrix, enhanced the thermal conductivity of the composites, and lowered the ablation temperature. The mass ablation rate and linear ablation rate of the CNFsmodified C/C composites are only 0.645 mg/s and 3.01 mu m/s, which are reduced by 21.6% and 28.8% respectively, indicating excellent ablation resistance. This work provides theoretical guidance for the large-scale preparation of nano-material modified C/C composites in the future.