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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.

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.

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]

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]

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]

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]

Potential techniques to identify small quantities of fissionable materials (FM) (0.001% wt.) in conditions of a high gamma background level have been reviewed and compared, and the optimal possibility for the nuclear material (NM) control in spent fuel assemblies (SFA) has been selected. It was found through numerical simulation that a system based on a passive neutron control method could be used to detect FMs indirectly when the spent nuclear fuel (SNF) burn-up and cooling time are known. Two types of detectors have been compared: 3He counters and 235U-based fission chambers. Better application prospects of 3He counters, based on the SNM-18 neutron counter, have been shown and drawbacks of passive control technique have been pointed out. An active neutron control has been found to be the best way to address the problem considered. The system's computational model shows that the signal exceeds the triple background error (both for ambient and intrinsic background from Cm isotopes) more than twelvefold. To improve the signal recording efficiency, the system has been modified to allow for irregularities in the geometrical position of structural materials (SM) in the measuring chamber. The proposed procedure makes it possible to determine in a short time the content of 239Pu, 242Cm, and 244Cm in an SFA. After the quantity of 239Pu is determined, it is possible to estimate the content of other isotopes (Am, U, Np) due to the constancy of the 239Pu mass ratio to the mass of the actinide identified.

To investigate the effect of Fe content on the correlation between the microstructure and mechanical properties in near-b titanium alloys, the Ti-5Al-5Mo-5V-1Cr-xFe alloy system has been characterized in this study. As the Fe content increased, the number of nucleation sites and the volume fraction of the α phase decreased. We observed a significant difference in the shape and size of the α phase in the matrix before and after Fe addition. In addition, these morphological deformations were accompanied by a change in the shape of the α phase, which became increasingly discontinuous, and changed into globular-type α phase in the matrix. These phenomena affected the microstructure and mechanical properties of Ti alloys. Specimen #2 exhibited a high ultimate tensile strength (1071 MPa), which decreased with further addition of Fe.

TiAl porous alloys exhibit potential for application in high-temperature flue gas filtration, because of their satisfactory mechanical properties and excellent high-temperature creep resistance. However, poor oxidation resistance and corrosion resistance at temperatures exceeding 800 °C considerably limit the practical applications of TiAl porous alloys. The disadvantages of TiAl alloys can be mitigated by adding a specific amount of alloying elements to delay oxygen diffusion. In this study, two kinds of porous alloys, Ti-48Al and Ti-48Al-2Nb-2Cr, are used to evaluate the high-temperature oxidation resistance and sulfidation resistance of TiAl-based porous alloys. With the addition of alloying elements Nb and Cr, the high-temperature oxidation resistance and sulfidation resistance of the TiAl alloys have greatly improved. The mechanisms underlying phase transformation are also explained using the first-principles theory. The excellent antioxidation and anti-sulfidation properties of the Ti-48Al-2Nb-2Cr porous alloy are mainly attributed to the markedly reduced free energy of Al2O3 formation and suppress the presence of TiO2 at elevated temperatures, as explained by first-principles calculations. The Ti-48Al-2Nb-2Cr porous alloy has advanced the application of multiple alloying in high-temperature flue gas filtration. [ABSTRACT FROM AUTHOR]

The influence of technological heredity factors on the quality indices of parts and products made of polymer composite materials is considered. A technique is developed to take into account the technological heredity factors using the theory of catastrophes. To formalize the technological heredity factors, we propose to use logical functions to form models to predict the change in the quality of a structural material during the entire life cycle of a product. The proposed models can be used to estimate the fracture kinetics for many materials qualitatively. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) fiber–reinforced SiC matrix (SiC/SiC) composites have been widely investigated for potential fusion reactor applications. In this present investigation, the high-temperature creep performance of five types of SiC fibers is evaluated and microstructural analysis is performed. The creep behavior of the fibers was assessed by the bend stress relaxation method at various applied strains at 1500°C and 1700°C. The fibers tested include developmental-grade fibers with different residual silicon amounts (~0%, 2% to 3%, and 5% to 6%) fabricated by laser chemical vapor deposition at Free Form Fibers. Generally, the creep behavior of the Free Form (FF) fibers was similar to Hi-Nicalon Type S and/Tyranno-SA SiC fibers currently used for fabrication of SiC/SiC composites for fusion applications. However, all FF fibers exhibited the formation of pores after the creep tests at 1700°C regardless of residual silicon amount, which can be improved by further development via optimization of the composition and microstructure. [ABSTRACT FROM AUTHOR]

Macroscopic properties of carbon fiber‐reinforced plastic (CFRP) and environmental barrier coating (EBC), widely used for airplanes, can be deteriorated by local cracks or degradation ("trigger sites"). We have tried to find these trigger sites using x‐ray microscopy (XM), which can provide the 2D or 3D images of the chemical states and microstructures. Crack initiation in CFRP was observed in a non‐destructive manner in multi‐scales (nm‐mm). 3D chemical‐state mapping of Yb in EBC was achieved with high resolution (<50 nm). In addition to XM, in‐situ observations at high temperatures were conducted for obtaining complementary information. X‐ray absorption spectroscopy (XAS) and x‐ray diffraction (XRD) analysis were performed simultaneously up to 1773 K. Dynamic XAS with short time‐resolution (<10 ns) was conducted to investigate changes in the local structure of metal. These approaches can help us identify degradation trigger sites in the materials. [ABSTRACT FROM AUTHOR]

Recent years have brought a rapidly growing demand in the civil engineering field for durable structural material which is also plant life friendly. Concrete has sufficient durability but lacks such friendliness. Soil is sufficiently plant life friendly but lacks durability. This research presents durable structural materials which are plant life friendly: Some cementitious structural materials mixed with rice husk ash, the powder left after rice husks are destroyed by burning for example. There are at least three phases in a material's life cycle: the production phase, the maintenance phase, and the disposal phase. These structural materials are designed to ensure good performance in all three phases; they are produced from an environmentally friendly by-product; they excel in permeability and water retentivity as well as in durability; and they decompose, causing only negligible damage to environments. Carbon dioxide emitted by burning rice husks was analyzed in the case of a power plant (cogeneration system) utilizing rice husks. These materials reduce carbon dioxide emissions by replacing cement with rice husk ash. This study will contribute to the low carbon societies. [ABSTRACT FROM AUTHOR]

Highlights • Corrosion mechanism of Ni-Co-based alloys in LiCl-Li 2 O molten salt is proposed. • Weight loss of alloys with low cobalt was less compared to those with high. • High content of Cr caused intergranular corrosion in the corrosion layer. • Excess Cr has a deleterious effect on kinetics during the hot corrosion process. Abstract In this study, hot corrosion behaviours of Haynes 282 (H282), Nimonic 90 (N90), and Haynes HR160 (HR160) in LiCl-Li 2 O molten salt were investigated at 650 °C under argon atmosphere. The corrosion rate was in the order of H282 < N90 < HR160, depending on the morphology and structure of the scale. H282 showed a localised corrosion behaviour, while N90 showed a uniform corrosion behaviour. For HR-160, intergranular corrosion was observed. The high Cr content caused intergranular corrosion in the corrosion layer. Thus, excess Cr has a deleterious effect on the corrosion kinetics during hot corrosion in LiCl-Li 2 O molten salt. [ABSTRACT FROM AUTHOR]

In this research work, cost-effective structural material synthesis routes have been adopted in the form of thermal cycling designed and applied on a low-cost material (AISI 1010 steel). The main synthesis route consists of two-step thermal cycling (designed with respect to iron–carbon phase diagram) combining short-duration holding in upper critical and intercritical temperature regimes and different cooling conditions (forced air cooling and ice-brine quenching). Accordingly, the adopted hierarchical design approach (from nanoscale onwards) with a combination of hard and soft phases (to attain an adequate balance between mutually exclusive strength and ductility properties) results in origin of a novel microstructure. The microstructure consists of dislocation-enriched martensite regions (possessing plate and lath morphologies in 1:4 ratio) containing nanosized cementite particles and α-ferrite regions containing submicroscopic cementite particles. As a consequence, an excellent combination of strength (UTS = 905 MPa) and ductility (%Elongation = 17) is achieved in the synthesized material. [ABSTRACT FROM AUTHOR]

Steel and concrete are traditionally used as structural materials for non-residential and multi-housing buildings. However, wood can meet the same structural property requirements, and a variety of multi-story buildings have recently been built all over the world using this key material. In this study, the main motivations and barriers to wood adoption for structural uses in non-residential buildings are highlighted, based on an analysis of grey literature concerning some well-known buildings and on scientific literature. The motivations found were linked to sustainability, lack of expertise, costs, rapidity of erection, and aesthetic of wooden structures. In contrast, the barriers preventing its use encompass building code implementation, technology transfer, costs, material durability and other technical aspects, culture of the industry, and material availability. Furthermore, an analysis of non-residential timber building meeting minutes for nine projects is also presented to support the identification of problems and concerns related to site assembly issues, the conception of the building, the scheduling, and stakeholders’ relationships. With a better understanding of the expectations and challenges concerning wood usage in non-residential construction projects, companies will be able to adapt their business models and use the resource even more in the future to develop innovative structures.

Abstract Scientists have been focused on fusion reactor studies to overcome the increasing energy demand. The materials, which have the potential to be used in fusion reactors must be resistant to the harmful effects of radiation in the manner of material itself. Selection of the appropriate materials to be used in nuclear reactors has a crucial importance to achieve the maximum efficiency and security. Ti, V, Ni and Cu are known as some of the constructional fusion materials. Existence of many knowledge about those materials provides countless advantages to the researchers and one of them is the cross–section, which basically means the probability of a nuclear reaction's occurrence. In addition to the cross–section, there exist some other parameters, which could be pointed as gamma strength function and level density models that affect the theoretical calculations. In this study, photon induced reaction cross–sections of 46,50Ti, 51V, 58Ni and 63Cu target isotopes have been calculated by using TALYS 1.8 code with different gamma strength functions in the giant dipole resonance region. For gamma strength functions Kopecky-Uhl generalised Lorentzian Model, Brink-Axel Lorentzian Model, Hartree-Fock BCS tables, Hartree-Fock-Bogolyubov tables and Goriely's Hybrid Model have been employed. To appoint the best gamma strength function model, the relative variance calculations have been performed. Also, reaction cross–sections have been recalculated by using the best gamma strength function models through the different level density options. Constant Temperature Fermi Gas Model, Back Shifted Fermi Gas Model and Generalised Super Fluid Model have been employed for level density calculations. Experimental data for the investigated reactions have been taken from EXFOR library and used for comparisons of the obtained calculation results. Highlights • Reaction cross–section calculations have been done for 46,50Ti, 51V, 58Ni and 63Cu isotopes. • Gamma strength functions and level density models effects on cross–section calculations have been investigated. • TALYS 1.8 code has been used in the calculations. • The models are validated using the experimental values from the literature. [ABSTRACT FROM AUTHOR]

Life Cycle Assessment (LCA) is increasingly used as an early-stage design-decision tool to support choices of structural system. However LCA modellers must first make numerous methodological decisions, and the resultant wide variations in approach are often inadequately described by the modellers. This paper identifies, and quantifies, the three major areas of methodological variation. These are: temporal differences in the stages considered; spatial differences in the material boundaries; and physical disparities in the data coefficients. The effects are then demonstrated through a case study of a student residential building in Cambridge. The cross-laminated timber (CLT) structure is compared with concrete frame, steel frame and load-bearing masonry, considering the influence that varying the temporal boundaries, the data coefficients, and the spatial boundaries has on the choice. While for this building CLT is confirmed as the lowest impact material, the paper demonstrates that varying the methodological choices can change the results by an alarming factor of 10 or even more. The findings confirm the need for the utmost clarity and transparency with all LCA calculations. Making wider industry or policy decisions based on LCA results should be undertaken with extreme caution. [ABSTRACT FROM AUTHOR]

This review describes existing methods of parametric definition of rubbers as structural materials, including the authors' own methods. The principal features of the non-linear mechanical behaviour of elastomer composites are set out. [ABSTRACT FROM AUTHOR]

Fusion energy is considered to be the ultimate energy source, which does not contribute to climate change compared with conventional fossil fuel. It is massive compared with unconventional renewable energy and demonstrates fewer safety features compared with unconventional fission energy. During the past several decades, never-ceasing efforts have been made to peacefully utilize the fusion energy in various approaches, especially inertial confinement and magnetic confinement. In this paper, the main developments of magnetic confinement fusion with emphasis on confinement systems as well as challenges of materials related to superconducting magnet and plasmafacing components are reviewed. The scientific feasibility of magnetic confinement fusion has been demonstrated in JET, TFTR, JT-60, and EAST, which instigates the construction of the International Thermonuclear Experimental Reactor (ITER). A fusion roadmap to DEMO and commercial fusion power plant has been established and steady progresses have been made to achieve the ultimate energy source. [ABSTRACT FROM AUTHOR]