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Poly(para‐xylylene) (PPX) is a robust and biocompatible coating material that is widely used in various applications, including electronics, aerospace and defense materials, automotive materials, and biomaterials. In this progress report, recent developments in PPX technology ranging from the advancement of physical chemistry properties and structural properties for device integration to the transformation of 3D monolith materials of PPX with controls in outer and inner structures at the micro‐ and nanometer scales are highlighted. Based on emerging chemistry studies on [2.2]paracyclophanes, which are primarily used precursors to synthesize PPX via vapor deposition polymerization, functionalization, and the creation of a wide variety of functional PPX derivatives are demonstrated without resistance. Widely used as an interface coating material, PPX is processed to form integrated structural materials and has already been found to be useful in the market as part of electronic and medical implant products. Using a newly innovated transformation to fabricate PPX through templates (metal‐organic frameworks, liquid crystal, ice crystal), 3D monoliths, nanoscale particles, hierarchical and gradient interior structures, and dynamically transformable shapes at the nanoscale are demonstrated. A vast landscape of novel applications and device products is expected based on the already established R&D and market maturity of PPX. [ABSTRACT FROM AUTHOR]

Advanced materials technology is the forerunner in the development of high-tech aerospace equipment and the key foundational technology supporting the modern industry. It has penetrated into all aspects of national defense construction，national economy and social life，and has become a technological highland and national defense focus that countries all around the world are competing to develop. This article focuses on analyzing the current technological status and development trend of the advanced structural materials in the aerospace field，elaborating on the aspects of high-performance polymer and their composites，high-temperature and special metal structural materials，lightweight high-strength metals and their composites，and advanced structural ceramics and their composites. The analysis results show that the current development and production of aerospace structural materials in China still face various difficulties，such as too much follow-up research and imitation，lack of independent innovation，severe technological blockade，and technical bottlenecks need to be broken. Meanwhile，the prospects for future research and development are proposed，and the significance of establishing the complete technology system of production-learning-research-application is highlighted.

This study was conducted to investigate the feasibility of using yellow poplar as a structural member by determining allowable bending properties. Full-size lumber was classified by machine grading and the knot diameter ratio on the wide surface of lumber. The majority of machine grades of yellow poplar lumber with a cross-section of 38 × 89 mm2 were E8, E9, and E10. It was confirmed that the size of the knot diameter ratio tended to be smaller for higher machine grades. In the lowest grade, E8, of most machine grades, the allowable bending strength was lower than the corresponding design value in Korean standards. Application of 0.5 knot diameter ratio to the E8 grade lumber increased the bending strength to 3 MPa of the allowable value to suit the design value. All the allowable modulus of elasticities values of the majority of machine grades were higher than the design values. From the results of this study, it was expected that Korean yellow poplar could be utilized for structural bending members.

Nowadays, the interaction of additive technologies and methods for designing or optimizing porous structures has yielded good results. Construction with complex microarchitectures can be created using this approach. Varying the microarchitecture leads to changes in weight and mechanical properties. However, there are problems with geometry reconstruction when dealing with complex microarchitecture. One approach is to use Voronoi cells for geometry reconstruction. In this article, an extension of the Voronoi diagram algorithm to orthotropic space for material structural design is presented. The inputs for the method include porosity, ellipticity, and ellipticity direction fields. As an example, a beam with fixed end faces and center kinematic loading was used. To estimate robust results for different numbers of clusters, 50, 75, and 100 clusters are presented. The porosity for smoothed structures ranged from 21.5% up to 22.8%. The stress–strain state was determined for the resulting structures. The stiffness for the initial and smoothed structures was the same. However, in the case of 75 and 100 clusters, local stress factors appeared in the smoothed structure. The maximum von Mises stress decreased by 20% for all smoothed structures in the area of kinematic loading and increased by 20% for all smoothed structures in the area of end faces. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Aeronautical Materials is the property of Editorial Board of Journal of Aeronautical Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An ODS steel with nominal composition Fe–14Cr–2W–0.4Ti-0.3Y2O3 (wt.%) was produced by mechanical alloying and compacted by hot isostatic pressing (HIP) followed by hot cross rolling (HCR). To check the effects of thermal aging at relevant temperatures of operation in fusion power plants, the alloy was thermally aged at 873 K for 2000 h. In this work, small-angle neutron scattering (SANS) and X-ray absorption spectroscopy (XAS) techniques are used for the advanced characterization of secondary phases and the oxide nanoparticle dispersion. SANS results show that the oxide nanoparticles remain stable after the thermal aging treatment. Composition of the oxide nanoparticles was identified as Y2TiO5 or Y2Ti2O7 by SANS, while non-stoichiometry was found by XAS analysis. Laves phase precipitation after the thermal aging treatment is further confirmed by SANS, from the magnetic anisotropic contribution to the scattering intensity associated to this metallic phase, and by XANES.

This study was conducted to confirm the feasibility of using yellow poplar, which is a fast-growing hardwood species in Korea, as a structural material. Lumber was produced, and the mechanical grading and the knot diameter ratio on the wide surface measurement were performed for each grade of lumber. It was confirmed that the majority mechanical grades of yellow poplar were E10, E11, and E12, and the size of knot in the surface increased as the mechanical grades decreased. A fitted distribution of tensile strength of the lumbers was the Weibull distribution. As a result of calculating the tensile allowable stress using the 5th percentile value calculated by the Weibull distribution and the non-parametric method according to the mechanical grade, all the experimental values were higher than the minimum allowable stresses presented in the Korean industrial standards. However, for the low grades, there was no significant difference from the standard values. This was thought to be due to the large size of knots in low-grade lumber. It was expected that the prospect of using yellow poplar structural member will be higher if additional research is conducted on the restriction of knot size according to the mechanical grade.

Tall timber buildings represent an emerging and highly promising sector due to their potential to yield significant environmental and economic advantages throughout their entire life cycles. Nonetheless, the existing body of literature lacks a comprehensive exploration of the primary architectural and structural design considerations for such sustainable towers. To address this gap and to enhance our understanding of emerging global trends, this study scrutinized data from 49 tall timber building case studies from around the world. The key findings revealed the following: (1) Europe stood out as the region boasting the highest number of tall timber buildings, with North America and Australia following behind; (2) residential applications were the most preferred function for tall timber buildings; (3) central cores were the predominant choice for core configuration; (4) prismatic forms were the most prevalent design preferences; (5) composite materials were notably widespread, with timber and concrete combinations being the most prominent; (6) structural systems primarily featured shear–frame systems, especially shear-walled frames. By unveiling these contemporary characteristics of tall timber buildings, this research is expected to provide valuable insights to architects, aiding and guiding them in the design and execution of future sustainable projects in this field. [ABSTRACT FROM AUTHOR]

High-rise residential timber buildings (≥8 stories) are an emerging and promising domain, primarily owing to their capacity to deliver notable environmental and economic benefits over the entire span of their existence. However, it is worth noting that the current body of scholarly work falls short in providing a thorough examination of the key aspects related to architectural and structural design for these environmentally sustainable towers. In an effort to bridge this knowledge gap and deepen our comprehension of the evolving worldwide trends, this research delved into data collected from 55 case studies conducted across the globe. The primary findings unveiled the following: (1) Europe, particularly Nordic countries, stood out as the region boasting the highest number of high-rise residential timber buildings, with North America and the United Kingdom following suit; (2) central cores were the prevailing choice for the core configuration, with the peripheral type following as the second most common option; (3) prismatic forms were the most commonly favored design choices; (4) widespread prevalence of employing pure timber was observed, followed by timber and concrete composite combinations; and (5) structural systems were predominantly characterized by the utilization of shear walled frame and shear wall systems. This research aims to reveal the current attributes of high-rise residential timber buildings, with the expectation that it will offer architects valuable knowledge to assist and steer them in planning and implementing forthcoming sustainable projects within this domain. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The threats of nonrenewable energy consumption and environmental disruption caused by the extensive use of metals and polymers derived from petroleum have prompted the development of eco-friendly, high-performance, and long-lasting structural materials. After various treatments, cellulose materials exhibit exceptional properties such as high strength, fire resistance, hydrophobic properties, and thermal stability. Cellulose-based structural materials have excellent mechanical strength and the distinct advantages of being lightweight, inexpensive, and energy efficient. This review summarizes the recent progress in the preparation methods and properties of high-performance cellulose structural materials such as high-strength cellulose structural materials, thermal insulation cellulose structural materials, flame-retardant cellulose structural materials, hydrophobic cellulose structural materials, cellulose structural material with electrical properties, and other cellulose structural materials. The future of high-performance cellulosic structural materials and the prospective of their development are concluded.

Nowadays, the interaction of additive technologies and methods for designing or optimizing porous structures has yielded good results. Construction with complex microarchitectures can be created using this approach. Varying the microarchitecture leads to changes in weight and mechanical properties. However, there are problems with geometry reconstruction when dealing with complex microarchitecture. One approach is to use Voronoi cells for geometry reconstruction. In this article, an extension of the Voronoi diagram algorithm to orthotropic space for material structural design is presented. The inputs for the method include porosity, ellipticity, and ellipticity direction fields. As an example, a beam with fixed end faces and center kinematic loading was used. To estimate robust results for different numbers of clusters, 50, 75, and 100 clusters are presented. The porosity for smoothed structures ranged from 21.5% up to 22.8%. The stress–strain state was determined for the resulting structures. The stiffness for the initial and smoothed structures was the same. However, in the case of 75 and 100 clusters, local stress factors appeared in the smoothed structure. The maximum von Mises stress decreased by 20% for all smoothed structures in the area of kinematic loading and increased by 20% for all smoothed structures in the area of end faces.

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, intensive investigations on the potential of rubberized concrete as a structural material are available in the literature due to its promising characteristic in terms of sustainability, ductility, high absorption of energy, and enhanced vibration behavior. These works have initiated the introduction of multiple estimation methods to rapidly evaluate its properties. Over the last few decades, hundreds of researches have been conducted to assess different mathematical approaches for modeling concrete's properties. Among them, multivariable regression analysis is considered one of the simplest multipurpose options. However, its adaptation is sometimes inefficient, and its results are not highly accurate. This study proposes an enhancement to the estimation technique for rubberized concrete's mechanical characteristics by conducting a data reconstruction using kernel principal component analysis and then utilizing multivariable regression to develop the prediction models. The importance of the kernel principal component analysis comes from its capability to transform the input parameters to visualize the dataset's information described by multiple inter-correlated quantitative variables so that it discovers underlying patterns. In general, the research results have shown that the performance of the proposed method can significantly overcome that of the conventional regression techniques with as high as 80% reduction in the root-mean-square error in the case of compressive strength. [ABSTRACT FROM AUTHOR]

Today, supertall buildings can be constructed in unusual forms as a pragmatic reflection of advances in construction techniques and engineering technologies, together with advanced computational design tools for architectural design. As with many other buildings, architectural and practical principles play a crucial role in the form of a supertall building, where aerodynamic behavior shaped by wind-induced excitations also becomes a critical design input. Various methods are used to meet the functional needs of these towers and reduce excitations, including aerodynamic modification methods directly related to the building form. Tapered forms are one of the most frequently used and most effective methods in today's skyscrapers, which significantly affect architectural design. To date, no study has been conducted in the literature that provides an understanding of the interrelationships between tapered building forms and main planning criteria, considering the aerodynamic design concerns of the tapering effect in supertall buildings (≥300 m). This important issue is explored in this article with data gathered from 41 supertall case studies, considering location, function, structural system, and structural material as well as the aerodynamic taper effect. The main findings of the study highlighted the following: (1) Asia was where tapered towers were most favored, with a wider margin in all regions; (2) mixed-use was the most preferred function in selected supertall buildings with tapered form; (3) outriggered frame systems were mainly used; (4) tapered supertall cases were mostly built in composite; (5) the sample group included 17 cases that used the tapering effect with aerodynamic design concerns, some of which were accompanied by corner modifications. It is believed that this study will be a basic guide for design and construction professionals including architectural and structural designers, and contractors.

Non-pneumatic tyre technology can overcome the safety problems of traditional pneumatic tyres. Hence, it is expected to improve driving safety significantly. Accordingly, in recent years, this technology has received extensive attention. This paper reviews the status of research of non-pneumatic tyres and discusses their development trends. Initially, the fundamental concept of non-pneumatic tyres is introduced, and their structural characteristics are described in detail. Subsequently, the research progress on the material properties of non-pneumatic tyre components is summarised. The research results on the mechanical properties of non-pneumatic tyres are recapitulated in terms of vertical mechanical, longitudinal mechanical, lateral mechanical, grounding, vibration, and fatigue characteristics. Moreover, the advantages and disadvantages of non-pneumatic tyres are analysed. Three prevailing forming technologies and tyre performance tests are discussed. The application of intelligent materials and structures to non-pneumatic tyres is proposed for these tyres to be lightweight, functional, and intelligent. Finally, the technical problems that must be resolved in the study of non-pneumatic tyres and the anticipated development trends are presented in this paper.

[Display omitted] • Structural integrity assessment of materials containing notch-type defects. • Combines Failure Assessment Diagrams and the Theory of Critical Distances. • Validated on 1106 experimental results from metals and non-metals. • The methodology provides safe reasonably conservative assessments. This paper provides a comprehensive description, and the subsequent validation, of a structural integrity assessment methodology of structural materials containing notch-type defects. The approach is based on the combination of Failure Assessment Diagrams (FAD) and the Theory of Critical Distances (TCD). The former provides the general assessment tool, which is exactly the same one as that used for crack-like defects, whereas the latter provides the notch effect correction required for the analysis of this type of defects. Finally, the proposed methodology is validated on a number of metallic and non-metallic structural materials, with 1,106 experimental results on different types of testing specimens, covering four structural steels, aluminium alloys 7075-T651 and 6060-T66, PVC, PMMA, PA6, fibre-reinforced PA6, 3D printed (Fused Filament Fabrication) ABS, PLA and graphene reinforced PLA, granite and limestone. The results show how the FAD-TCD methodology provides safe reasonably conservative assessments on the mentioned structural materials in the presence of notch-type defects. [ABSTRACT FROM AUTHOR]

Molten chloride salts are promising fluids for use in molten salt reactors (MSRs) and concentrated solar power (CSP) systems. Hence, understanding the corrosion phenomenon caused by individual chloride salts is essential to determine their effect on the corrosion of structural alloys. This study aimed to explore the corrosion behavior of nickel-based alloys, namely alloys 600, 617, and Hastelloy N, in individual KCl salt. The findings demonstrated that the corrosion of all alloys in molten KCl salt primarily results from the preferential dissolution of the Cr element along grain boundaries, leading to the formation of pits. Furthermore, the corrosion rate was estimated to be 53.2 μm/year for alloy 600, 104.5 μm/year for alloy 617 with the fastest, and 34.8 μm/year for Hastelloy N with the slowest. These results indicate that Hastelloy N with the lowest pristine Cr content exhibits excellent corrosion resistance compared to alloys 600 and 617 in molten KCl salt. • Studied Ni-based alloys in molten KCl salt at 800 °C using various techniques. • Comprehensive analysis elucidates corrosion behavior. • Cr dissolution along grain boundaries led to pit formation on alloy surfaces. • Higher Cr content accelerates alloying element consumption in molten KCl salt. • Hastelloy N showed superior corrosion resistance due to lower Cr content. [ABSTRACT FROM AUTHOR]

From several countries trend bamboo has been used as a scaffolding material in building projects. Nonetheless, Ethiopia is known for the high population of bamboo vegetation such utilization of the material remained untapped. The purpose of this paper is to identify factors that influence bamboo’s structural suitability as a temporary material and to create a conceptual map for using it as an alternative structural material. Following the identification of important applications influencing parameters via literature analysis, both qualitative and quantitative approaches were used to identify significant factors. The paper also used a series of protocols; at first, several documents were selected based on criteria to provide an overview of bamboo-based construction systems. Following that, four major categories for SWOT analysis were chosen to examine the Ethiopian construction industry’s stance on the use of bamboo as a scaffolding material. Finally, a scoring model was employed as a quantitative analysis protocol to calculate the weight of factors (safety, procedure and implementation, time, and cost) through expert opinions. The investigation revealed that the use of bamboo has a cost and time savings advantage, while an increase in trash at acute and intermittent areas was one of the challenges. Furthermore, one of the challenges in creating bamboo formwork is a lack of complementary joinery techniques. Besides that, it is expected that the bamboo content will fall short of technical requirements. On the Brightside, every single respondent stated unequivocally that bamboo-made formwork meets a low-cost requirement.

The purpose of this study is to observe the change in the microstructure of the magnesium AZ91 alloy with the help of refinement of the grain structure due to Friction Stir Processing (FSP), resulting in to a change of mechanical behaviour. During FSP, effect of the variation of tool rotational speed was also investigated. The microstructural and mechanical behaviour of the prepared samples before and after FSP were investigated with the help of X-Ray Diffraction (XRD), Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Microhardness test and Tensile test. The base initial material's (Magnesium Alloy AZ91 grade) microstructure consists of irregularly distributed secondary phases (Al12Mg17) along the grain boundaries and within the grains, while the FS Processed samples show the regular and uniform grains with the dissolution of the secondary phase. The improvement in the hardness and tensile strength was observed after Friction Stir processing of the samples' with the variation of Tool rotational speed. The Ultimate Tensile Strength (UTS) and percentage elongation of samples processed at 1160 rpm were increased by approximately 56% and 118% as compared to the base material. [ABSTRACT FROM AUTHOR]

The pursuit of harnessing superior mechanical properties achieved through the size effect on a macroscopic scale has been a prominent focus in engineering, as size-induced strengthening is enabled only in the nanoscale regime. This study presents a metal/ceramic/metal (MCM) nanocomposite reinforced by ceramic nanoarchitectures. Through proximity-field nanopatterning, the inch-scale production of nanoarchitecture films is enabled in a single fabrication step. The developed three-dimensional (3D) Ni/Al 2 O 3 /Ni nanocomposite film exhibits significantly high compressive strength, corresponding to an increase of approximately 30% compared with that calculated using the upper limits of the conventional rule of mixtures. The exceptional strength of the 3D MCM nanocomposite can be attributed to the extrinsic size effect of the ceramic nanoarchitectures. By combining size-induced strengthening of ceramics with the strengthening law for composites, a new type of strengthening model is derived and experimentally validated using the 3D MCM nanocomposite.

The studies on rubberized concrete have increased dramatically over the last few years due to being an environmentally friendly material with enhanced vibration behavior and energy dissipation capabilities. Nevertheless, multiple resources in the literature have reported reductions in its mechanical properties directly proportional to the rubber content. Over the last few years, various mathematical models have been proposed to estimate rubberized concrete properties using artificial intelligence, machine learning, and fuzzy logic-based methods. However, these models are relatively complicated and require higher computation efforts than multivariable regression ones when it comes to the daily usage of practicing engineers. Additionally, most of the study has mainly focused on the compressive strength of rubberized concrete and rarely went into more details considering other properties and sample sizes. Therefore, this study focuses on developing simple yet accurate rubberized concrete multivariable regression models that can be generalized for various mixtures of rubberized concrete considering different sample sizes.

• Spruce-inspired structural material was made by rotational co-extrusion 3D printing. • The printed filament was knitted in a double helix of stiff and soft resins. • Spruce-inspired structural material showed superb tunable mechanical properties. Spruce branches have a continuous gradient in the microfibril angle of helically entwined cellulose fibrils in their internal cell walls, which confers the modulation of the site-specific mechanical properties. This paper draws inspiration from the microstructure within spruce branches and successfully fabricates a biomimetic structural material assembled from stiff and soft resins in a double-helix distribution using rotational co-extrusion 3D printing. The tunability of the mechanical properties of the helical structural material can be achieved by regulating the helical degree and ratio of two resins in the extrusion filament in real-time. Additionally, a strategy for controlling failure is proposed through dynamic programming of the local structure within the printed sample. Furthermore, compared with the homogeneous beam, the prepared spruce-like beam can effectively mitigate stress concentration during the loading process, achieving greater deformation capacity. This helical structural material is expected to meet customized mechanical performance requirements and enrich the bionic structural material system. [ABSTRACT FROM AUTHOR]

Bamboo is an important forest resource in China. It is widely distributed in China, especially in the south, and its area and output rank first in the world. Although the bamboo industry has developed vigorously in recent years, a large part of small-diameter bamboo and moso bamboo processing residues have not yet been effectively used. This paper focuses on the research on the basic unit preparation of bamboo bundles of bamboo-based recombined structural materials, assembling technology, manufacturing process technology, composite recombination technology, main mechanical performance testing and bending performance, combined with actual production and application, focusing on research The key process technology of bamboo-based re-combined structural material manufacturing, and the following conclusions are drawn: through the re-search on the influence of the forming process fac-tors of the bamboo-based composite structure material, the process parameters for the best blank assembly effect are optimized. Taking into account that the higher the drying temperature, the greater the impact on the degree of curing of the adhesive and the greater the loss of the mechanical strength of the sheet. Therefore, the drying temperature of the dipped bamboo bundle is 50°C, and the moisture content of the bamboo bundle is 12% when forming the blank. The compression rate is 60%, the slab drying temperature is 50°C and the slab holding time is 5min, which are the experimental optimum forming process parameters for bamboo bundles. Through the research and exploration of the production process of bamboo-based reconstituted wood, the basic unit preparation process is optimized, the blank forming method that can be produced on a large-scale industrial scale is proposed, the traditional dipping process is improved, and the hot-pressing process is optimized. The comprehensive utilization rate of bamboo materials can reach 90%, which effec-tively reduces the production cost of bamboo-based restructured structural materials. [ABSTRACT FROM AUTHOR]

From several countries trend bamboo has been used as a scaffolding material in building projects. Nonetheless, Ethiopia is known for the high population of bamboo vegetation such utilization of the material remained untapped. The purpose of this paper is to identify factors that influence bamboo’s structural suitability as a temporary material and to create a conceptual map for using it as an alternative structural material. Following the identification of important applications influencing parameters via literature analysis, both qualitative and quantitative approaches were used to identify significant factors. The paper also used a series of protocols; at first, several documents were selected based on criteria to provide an overview of bamboo- based construction systems. Following that, four major categories for SWOT analysis were chosen to examine the Ethiopian construction industry’s stance on the use of bamboo as a scaffolding material. Finally, a scoring model was employed as a quantitative analysis protocol to calculate the weight of factors (safety, procedure and implementation, time, and cost) through expert opinions. The investigation revealed that the use of bamboo has a cost and time savings advantage, while an increase in trash at acute and intermittent areas was one of the challenges. Furthermore, one of the challenges in creating bamboo formwork is a lack of complementary joinery techniques. Besides that, it is expected that the bamboo content will fall short of technical requirements. On the Brightside, every single respondent stated unequivo- cally that bamboo-made formwork meets a low-cost requirement. [ABSTRACT FROM AUTHOR]

This paper investigates an efficient iron loss calculation method for soft magnetic materials of power transformers. To accurately estimate iron losses in the materials such as structural steels and magnetic shielding, the magnetic field analysis taking account of the nonlinear magnetic properties is considered to be effective. In this paper, quasi‐DC magnetic properties of the soft magnetic materials are measured and the iron losses are calculated by using a three‐dimensional finite element method. Furthermore, the effect of considering hysteretic properties on the accuracy of the iron loss calculation is discussed based on a theoretical representation of eddy current loss in a conductive rectangular plate. [ABSTRACT FROM AUTHOR]

Spider silk is a kind of natural biomaterial with superior performance. Its mechanical properties and biocompatibility are incomparable with those of other natural and artificial materials. This article first summarizes the structure and the characteristics of natural spider silk. It shows the great research value of spider silk and spider silk bionic materials. Then, the development status of spider silk bionic materials is reviewed from the perspectives of material mechanical properties and application. The part of the material characteristics mainly describes the biocomposites based on spider silk proteins and spider silk fibers, nanomaterials and man-made fiber materials based on spider silk and spider-web structures. The principles and characteristics of new materials and their potential applications in the future are described. In addition, from the perspective of practical applications, the latest application of spider silk biomimetic materials in the fields of medicine, textiles, and sensors is reviewed, and the inspiration, feasibility, and performance of finished products are briefly introduced and analyzed. Finally, the research directions and future development trends of spider silk biomimetic materials are prospected.

Abstract Wood as an ecofriendly and renewable natural material has been extensively modified through various delignification protocols to preserve its natural structure and fiber direction. The increased porosity and permeability of wood scaffold thus provide excellent opportunities for material infiltration and densification. Wood features in hierarchical structure and biocompatibility are combined with cutting‐edge processings to overcome the weaknesses for vast applications. These new modifications have explored the great potentials of wood as a next‐generation structural and functional material. This review updates the state‐of‐the‐art physicochemical modifications and strategies to prepare versatile wood hydrogels, aerogels, membranes, and fibers with different physicochemical features. Discussion is elaborated to explore the immense breadth of wood as next‐generation material for applications in biomedical, energy storage, sensors, separation, and buildings. Finally, the main challenges of wood scaffold engineering are represented along with potential solutions and directions for developing wood‐based high‐performance structural and functional materials.

Microwave sintering is regarded as a high-efficiency, energy-saving, and rapid-heating technique for the preparation of structural materials on the Moon. However, the influencing factors (i.e., ilmenite content and sintering temperature) on microwave sintering processes are not well-understood. Herein, five lunar regolith simulants with different contents of ilmenite (i.e., 4.6%, 28.5%, 43.9%, 65.8%, and 80.9% by weight) were used for microwave sintering experiments at 1,050°C, 1,150°C, and 1,300°C. The characterization of the microstructure, mineralogy, thermal conductivity, and mechanical properties of the products shows that the ilmenite content and sintering temperature significantly affected the properties of the microwave-sintered products. The sintering product containing 4.6% by weight ilmenite at 1,300°C showed a dense texture, good thermal insulation properties (thermal conductivity of 0.15±0.005 W m−1 K−1), and optimal compressive strength (74.0±7.1 MPa). This suggests that adding ilmenite to lunar regolith does not improve the properties of microwave-sintered products. The results in this paper provide reference for the preparation of structural materials on the Moon in the future. [ABSTRACT FROM AUTHOR]

Mg alloys are promising structural materials in aerospace industry due to high strength to weight ratio. However, most Mg alloys are limited in aircraft cabins due to their susceptibility to ignition and burning. To improve fire resistance, adding alloying elements is a strategy. Thus, the goal of this study is to explore the effects of alloying elements Al, Zn, and rare earths on Mg-alloy flammability by experiment, using the system and procedures in compliance with the Federal Aviation Administration (FAA) standards for Mg-alloy flammability test. Six commercial Mg alloys with different alloying elements (AZ91E, ZK61A, ZE63A, EZ33A, WE43B, and EV31A) were tested. Results indicate that Mg alloys with Al or Zn elements were of short ignition time and high weight loss. With rare earths, Mg-alloy flammability was suppressed obviously. It appears that this suppression effect with rare earth addition was attributed to the formation of protective oxide film on the surface of molten alloy. Further, a heat transfer model was established to analyze the temperature evolution of the test specimen subjected to the sonic burner–generated flame by FAA standards, and ignition temperatures of all testing Mg alloys were predicted based on the experimental ignition time. The predicted results confirm that with rare earths addition, ignition was delayed after melting by the protective oxide film formed on the surface of the molten alloy. [ABSTRACT FROM AUTHOR]

To alleviate the environmental pressure, it is of great significance to develop the green and sustainable structural materials by utilization of waste biomass. In this work, an eco-friendly, high-strength, superhydrophobic, and thermally stable material was fabricated through a scalable binder-free lamination method using waste biomass (e.g., wood residues, crop straw, and waste paperboard). The waste biomass was separated and molded into fiber mats by a clean pulping process, and then laminated without adhesives. The finite element method (FEM) was adopted to visually observe fracture behaviors and detect the weakest zones. The utilization of FEM to enhance the mechanical strength is unique in productions of traditional biomass composites. The weakest zones were reinforced by the H 2 O 2 spraying approach, and the flexural strength (FS) was improved from 80.12 to 120.35 MPa. The moisture content (MC) in the mat was used for regulating the softening of cellulosic fibers. In virtue of the water-induced plasticization, the laminated materials showed a high internal bonding strength (IBS) of 2.24 MPa and excellent FS of 134.81 MPa. Being benefitted from the silica modification, the materials exhibited a superhydrophobic surface with the high water contact angle (154.1°), good dimensional stability (a thickness swelling of 14.8%), and superior mechanical stability (remained 94.3% FS after two months of ultraviolet radiation). This work provides a new strategy to develop green and sustainable structural materials for buildings, furniture, and related applications. • Eco-friendly structural materials developed via binder-free lamination of waste biomass. • Incorporation of finite element method to visually observe fracture behaviors. • Improvement of interface bonding strength via H 2 O 2 spraying treatment. • High flexural strength of 134.81 MPa due to water swelling and partial removal of lignin. • Superhydrophobic performance and good dimensional stability benefitting to the silica modification. [ABSTRACT FROM AUTHOR]

A brief overview of the practical use of the new construction material of MONICA is given. An experimental study was performed for the first time on the analysis of the influence of the microstructural state on fatigue resistance. It is established that the fatigue limit of this material, based on 108 cycles, is not lower than 243 MPa. The role of the stress concentration in the vicinity of nonmetallic (graphite) inclusions on the formation of the fatigue resistance of MONICA is discussed. The ways of possible increase of the fatigue limit of this material up to ∼300 MPa and more are indicated.

The problems of manufacturing the working equipment of road machines from polymer composite materials (PCMs) are considered. The design of a bulldozer blade made of carbon-filled plastic with a honeycomb filler is proposed. The use of PCM with a honeycomb filler in its design is shown to decrease the specific amount of metal per product and to provide adaptation of the working bodies to various categories of developed soils, which significantly increases the productivity of machines. A list and range of changing the adaptable blade parameters, which affect the resistance of the soil to digging and dragging, are given. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS), also known as pulsed electric current sintering (PECS) or field-assisted sintering technique (FAST), belongs to a class of powder metallurgy techniques. In SPS, the sample is simultaneously subjected to a uniaxial pressure and electrical current in a vacuum or protective atmosphere. Although the fundamental principles of this procedure were first proposed over 50 years ago, SPS acquired major importance only within the last 20 years. Scholars come to realize that SPS technique enables control of the powder surface condition, atomic diffusion behavior, and phase stability and crystal growth behavior, as well as accelerating densification of hard-to-sinter materials. This review summarizes the latest research findings with respect to experimental procedures, densification behaviors, microstructural characteristics, and mechanical properties of various traditional and novel materials synthesized using SPS, mainly highlighting the heating mechanisms in SPS and the effects induced by multi-physical fields on materials. In addition, influences of operating parameters containing current, voltage, and uniaxial pressure on product characteristics are reviewed for a wide range of materialsincluding hard-to-sinter materials, carbon-containing materials, nanocrystalline materials, non-equilibrium materials, gradient materials, interconnect materials, complex shape materials, and advanced functional materials.

On the basis of specific irradiation conditions in fusion reactor, the advantages and limitations of the main proposed irradiation facilities including ion irradiation, fission neutron irradiation, spallation neutron irradiation and fusion neutron irradiation were compared and evaluated.Ion accelerators, fission reactors and theory and modeling are expected to continue to play an indispensable role in studying the irradiation effect of fusion materials before the 14MeV neutron source is available. The corresponding relation between irradiation data from real fusion neutron and irradiation data from ion, fission neutron or spallation neutron irradiation has to be verified by irradiation using 14MeV high flux neutron source (e.g. IFMIF). The construction of powerful, economy-efficient fusion materials irradiation facility and the development of multi-scale numerical simulation are the inevitable choices to facilitate the commercialized application of fusion materials.

Complex, concentrated alloys (CCAs) containing refractory principal elements and Al can have microstructures with disordered body-centered cubic (BCC) and ordered B2 phases that are remarkably similar to superalloys. The simple idea of copying superalloy microstructures in these BCC-based refractory alloys introduces a set of audacious challenges. BCC metals and B2 compounds are often brittle at room temperature; the B2 phase is unstable in refractory-Al binaries and reasons for its stability in higher-order systems are a mystery; and many refractory metals and alloys display catastrophic oxidation. Here we discuss opportunities and challenges to develop RSAs as new high temperature structural materials. Image, graphical abstract [ABSTRACT FROM AUTHOR]

This research investigates the reliability of Anogeissus schimperi timber specie grown in North Western Nigeria as a bridge beam in shear and bearing forces. Specimens for laboratory tests were prepared using the timber specie in accordance with BS 373 (1957). Tests were carried out to determine the physical and mechanical properties at 12% moisture content in line with BS 5268 (2002). Statistical analysis was carried out using strength properties obtained and the specie was classified to strength class D60, confirmed to be Hardwood. Anogeissus schimperi timber bridge beam was designed in accordance to BS5268 (2002), using deterministic approach. While, reliability analysis to confirm the safety level of the timber bridge beam designed was carried out using constant failure rate model in accordance with Jimoh, (2018). Sensitivity analysis to ascertain the safety margin of a simply supported timber bridge beam subjected to Shear and bearing by varying the span, depth, width and live load was carried out. Results of reliability analysis showed that Anogeissus schimperi met the minimum reliability index of 0.5 under ultimate state of loading in Shear and bearing. Safety index was found to be directly proportional to the depth and width but inversely proportional to the span and live load of the timber bridge beam during Sensitivity Analysis. The result confirmed that Anogeissus schimperi specie from north western Nigeria at 400mm depth, 150mm breadth and 5000mm span under ultimate limit state loading in Shear and bearing can be used as a reliable timber bridge beam material. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Lightweight structural materials are important for the energy efficiency of applications, particularly those in the building sector. Here, inspired by nature, we developed a strong, superhydrophobic, yet lightweight material by simple in situ growth of nano‐SiO2 and subsequent densification of the wood substrate. In situ generation of SiO2 nanoparticles both inside the wood channels and on the wood surfaces gives the material superhydrophobicity, with static and dynamic contact angles of 159.4o and 3o, respectively. Densification of the wood to remove most of the spaces among the lumen and cell walls results in a laminated, dense structure, with aligned cellulose nanofibers, which in turn contributes to a high mechanical strength up to 384.2 MPa (7‐times higher than natural wood). Such treatment enables the strong and superhydrophobic wood (SH‐Wood) to be stable and have excellent water, acid, and alkaline resistance. The high mechanical strength of SH‐Wood combined with its excellent structural stability in harsh environments, as well its low density, positions the strong and superhydrophobic wood as a promising candidate for strong, lightweight, and durable structural materials that could potentially replace steel. [ABSTRACT FROM AUTHOR]