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Functional structures that combine thermal protection with load‐bearing capabilities represent an effective solution to hypersonic thermal‐protection challenges. Here, we propose a Janus‐like bio‐inspired strategy for integrally 3D‐printed bimetallic metamaterials. Inspired by shell bilayers, a heat‐resistant AlSiFeMnNiMg alloy and a SiC‐reinforced AlSi10Mg are arranged as an architected pair and fabricated via dual‐hopper selective laser melting, with SiC volume fractions of 0, 4, and 8 vol%. In situ SEM tensile tests at 25°C and 250°C show that damage is confined to a narrow transition zone. Once one side softens, the bimetallic architecture redirects load to the other, forming non‐percolating high‐stress paths and stabilizing the plateau response. Quasi‐static compression of Gyroid TPMS lattices with different SiC contents maps the composition‐temperature space. Across temperatures, structures with 4 vol% SiC improve specific energy absorption by 11.72% and 18.67% in room temperature and by 10.28% and 18.8% in 250°C, achieving synergistic mechanical improvement and a stable energy‐absorbing plateau under extreme environments. Relative to 0 and 8 vol%, where modulus mismatch precipitates premature localized collapse, 4 vol% SiC promotes a distributed shear‐band network that delays failure and elevates load capacity. This work provides a practical pathway toward thermally protective and load‐bearing integrated components for aerospace applications. A Janus‐like bio‐inspired strategy is proposed for integrally 3D‐printed bimetallic metamaterials. Inspired by shell bilayers, a heat‐resistant AlSiFeMnNiMg alloy and a SiC‐reinforced AlSi10Mg with different SiC volume fractions are arranged as an architected pair. Across temperatures, structures with 4 vol% SiC achieve greatest synergistic mechanical improvement under extreme environments, opening a design space for thermally protective and load‐bearing integrated components.

Microsupercapacitors (MSCs) are vital power sources for internet of things (IoTs) and miniaturized electronics. The performance of MSCs is often restricted by its low areal energy density, which is due to the low areal mass loading of active materials. Constructing thick planar microelectrode with fine structure and high aspect ratio is an efficient way to increase mass loading, but limited by the breakable nature of porous electrode materials. Here, it is found that the mechanical and electrical properties of porous electrodes, as well as their surface area utilization and internal ion diffusion pathway, can be synergistically tuned by infilling gel electrolyte into internal pores of porous electrode films. The tuned thick porous electrode films are robust enough to enable laser ablation of three dimensional (3D) microelectrodes for high mass loading and high aspect ratio. The areal capacitance of 3D microelectrodes is able to increase linearly with mass loading (or thickness) up to at least 13 mg cm−2 (or 260 µm) for a value of up to 4640 mF cm−2 based on active carbon. The 3D MSCs deliver areal energy density of 1318 μWh cm−2, which is comparable to the best of Li‐ion 3D microbatteries while exhibiting superior electrochemical and mechanical stability. The mechanical and electrical properties of thick electrode films are tuned by infilling gel electrolyte, enabling laser ablation of 3D microsupercapacitors (MSCs) with high mass loading and high aspect ratio. The MSCs deliver an energy density of 1318 μWh cm−2, comparable to the best of microbatteries while exhibiting a superior power density of 102 mW cm−2 with high mechanical and cycling stability.

In this paper, a two-dimensional characteristic unit was used to simulate the thermal–mechanical performance of a fully ceramic microencapsulated (FCM) fuel pellet, and the criterion of FCM structure integrity was discussed. FCM structure integrity can be reflected though the integrity of the silicon carbide (SiC) matrix or SiC layers because of the excellent fission retention capability of SiC ceramics. The maximum temperature of the SiC matrix under normal conditions of the pressure water reactor (PWR) environment was about 1390 K, which was lower than the decomposition point of SiC. The maximum hoop stress of the SiC matrix, especially the inner part, was up to about 1200 MPa, and the hoop stress of the non-fuel region part was lower than the inner part, which can be attributed to the deformation of tristructural-isotopic (TRISO) particles. The hoop stress of the SiC layers at the end of life was only about 180 MPa, which is much lower than the strength of the chemical vapor deposition (CVD)-SiC. The failure probability of the SiC layer was lower than 9 × 10−5; thus, the integrity of SiC layers and the fission retention capability were maintained. The structure integrity of FCM fuel was broken because the SiC matrix cracked.

In the field of hybrid natural fiber polymer composites, there has been a recent surge in research and innovation for structural applications. To expand the strengths and applications of this category of materials, significant effort was put into improving their mechanical properties. Hybridization is a designed technique for fiber-reinforced composite materials that involves combining two or more fibers of different groups within a single matrix to manipulate the desired properties. They may be made from a mix of natural and synthetic fibers, synthetic and synthetic fibers, or natural fiber and carbonaceous materials. Owing to their diverse properties, hybrid natural fiber composite materials are manufactured from a variety of materials, including rubber, elastomer, metal, ceramics, glasses, and plants, which come in composite, sandwich laminate, lattice, and segmented shapes. Hybrid composites have a wide range of uses, including in aerospace interiors, naval, civil building, industrial, and sporting goods. This study intends to provide a summary of the factors that contribute to natural fiber-reinforced polymer composites’ mechanical and structural failure as well as overview the details and developments that have been achieved with the composites.

Optically transparent wood combines mechanical performance with optical functionalities is an emerging candidate for applications in smart buildings and structural optics and photonics. The present review summarizes transparent wood preparation methods, optical and mechanical performance, and functionalization routes, and discusses potential applications. The various challenges are discussed for the purpose of improved performance, scaled-up production and realization of advanced applications. This article is part of a discussion meeting issue ‘New horizons for cellulose nanotechnology’.

Polyesters based on 2,5-furandicarboxylic acid (FDCA) are a new class of biobased polymers with enormous interest, both from a scientific and industrial perspective. The commercialization of these polymers is imminent as the pressure for a sustainable economy grows, and extensive worldwide research currently takes place on developing cost-competitive, renewable plastics. The most prevalent method for imparting these polymers with new properties is copolymerization, as many studies have been published over the last few years. This present review aims to summarize the trends in the synthesis of FDCA-based copolymers and to investigate the effectiveness of this approach in transforming them to a more versatile class of materials that could potentially be appropriate for a number of high-end and conventional applications.

Ancient Chinese covered bridges are attracting increased attention due to their architectural appearance and manufacturing technique. In this study, an ancient single-arch covered bridge, Yinjia bridge, in Peach Blossom Spring in China has been investigated, mainly in the field of its cultural background, art aesthetics, and mechanical behavior. The methods of field measurement and finite element analysis were combined. First, the structural dimensions and construction of Yinjia bridge are introduced. Then, the historical origin and cultural connotation, the bridge corridor and decoration are considered, and the Chinese culture reflected behind the bridge design are investigated. A finite element model was built to study the mechanical behavior of the bridge. The numerical results indicate that the maximum vertical deflection of 4.32 mm is under but close to the limit of L/600, while no horizontal deflection exists at the foot of the arch crown. The maximum and minimum normal stress of 0.04 MPa and -0.12 MPa in components of bridge corridor are much less than the ultimate values of wood. The maximum compressive stress of 0.05 MPa of the bridge arch is within the limit value of the ultimate compressive strength of stone. This means that the structural safety performance of this ancient bridge is acceptable, and indicates that no significant structural damage has been found yet in the Yuxian bridge.

Semiconductor packaging is trending towards a miniaturisation in size but an increase in functionality. Hence, the thickness of the silicon wafer has decreased dramatically with a concern on the possible degradation of the strength of the thinned wafer. In this paper, 3-point bend (3PB) on bare silicon is selected as the preferred silicon break strength (SBS) test methodology due to its setup effectiveness and subsequent application in the prediction study. This experimental testing study focused on evaluating the SBS from different thickness ranges. The study was then followed by evaluating the influence of a possible impact from flaw creation with laser marking on silicon surfaces. The results show that the SBS is consistent although with significant differences in the silicon thickness ranges. It is also revealed that the onset breaking load may not be a suitable metric and could be over sensitive on gauging the SBS comparison. The flaw creation from the engraving process revealed a significant drop of 75% SBS although with an approximate depth removal of <10% from the total thickness. The consistence failure mode is clearly visible and this left the silicon very vulnerable to catastrophic failure. This indicates that extra care is needed on ultra-thin silicon during the assembly process as fractures may happen even before any reliability stress test is conducted. Furthermore, the completion of the package level 3PB failure mode verification has helped to demonstrate that an SBS study can be conducted with a simplified bare silicon level testing. In short, the study with this simplified 3PB has successfully proven its usefulness in SBS estimation. The observed ultra-thin silicon SBS has degraded and strongly depended on the critical flaws especially from the surface defect and impact from the assembly handling.

This research examines the effect of sodium hydroxide (NaOH) concentration on the synthesis, the physical and mechanical characteristics of metakaolin-based geopolymer mortars. Geopolymers were cured at 65?C with different NaOH molarities (6-16 M), and their bulk density, total porosity, compressive strength, and flexural strength were meticulously analyzed. The inquiry used sophisticated microstructural analysis by X-ray diffraction (XRD) to elucidate significant phase shifts and structural alterations. The findings indicate that the geopolymers produced with both lower and higher NaOH concentrations had enhanced physical and mechanical capabilities. XRD examination verified the existence of predominant crystalline phases of metakaolin and the development of a novel amorphous geopolymeric phase. This thorough methodology elucidates the ideal circumstances for improving geopolymer efficacy, offering significant insights for advanced material innovation.