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Driven by a curiosity of how sulfur (S) alters the physical properties of KTaO 3 , we embarked on a computational journey using the WIEN2k code and the insights of density functional theory (DFT). We aim to unravel the influence of S-substitution on the material's structure, electronic behavior, optical responses, mechanical strength, and thermodynamic characteristics of KTaO 3. Our investigation has unveiled a remarkable structural transformation, wherein the cubic phase of KTaO 3 undergoes a shift to a tetragonal configuration for KTaO 2 S and KTaOS 2 , eventually returning to a cubic phase in KTaS 3. Significantly, the band gap values have undergone substantial alterations, presenting energy gaps of 1.808 eV, 0.264 eV, and 0.078 eV for KTaO 2 S, KTaOS 2 , and KTaS 3 , respectively, diverging from the original band gap of 3.572 eV in KTaO 3. Importantly, all these compounds have exhibited mechanical and dynamical stability. Furthermore, these compounds have displayed promising optical features characterized by high absorption coefficients (∼105 cm−1), minimal reflectivity (<30%), and robust optical conductivity within the visible spectrum, making them ideal candidates for a range of optoelectronic technologies. Our comprehensive investigation has reinforced the stability of all computed phases, showcasing exceptional electronic, optical, and thermo-mechanical properties, including semiconducting behavior, hardness, ductility, anisotropy, high absorptivity, and low reflectivity. The modified band gap and optical characteristics of KTaO 2 S indicate considerable potential for its application in solar cells, presenting promising opportunities to improve solar energy conversion efficiency. The thermal conductivity of KTaO 3 is fascinating and shows substantial promise for applications as a heat sink material. • The effect of S substitution on the physical properties of KTaO 3 has been studied. • The band gap reduced significantly from 3.572 eV (KTaO 3) to 1.808 eV, 0.264 eV, and 0.078 eV for KTaO 2 S, KTaOS 2 , and KTaS 3. • The band gap and high absorption coefficient of KTaO 2 S indicate its potential for application in solar cells. • The thermal conductivity of KTaO 3 indicates its substantial promise for applications as a heat sink material. [ABSTRACT FROM AUTHOR]

• Novel method is applied to fabricate SiC fiber-reinforced Al matrix composites. • SiC fibers with high volume fraction is introduced into the Al matrix uniformly. • SiC fiber significantly improve the mechanical properties of Al matrix composites. • Coefficient of thermal expansion decreases with increasing the SiC fibers' content. Combining the colloidal dispersion method with the squeeze melt infiltration technique, aluminum matrix composites with different volume fractions of silicon carbide fiber were fabricated at 680 °C under vacuum. Microstructure analysis found that composite presented a dense structure and fibers were homogeneously distributed in matrix. The hardness, yield strength and elastic modulus of the composite monotonically increased with increasing the volume fraction of fiber. The highest flexural strength for composite with 10 vol% SiC fiber was achieved. The improved mechanical properties could be attributed to the dispersion strengthening and enhanced load transferring ability by fibers as well as the dislocation strengthening. On the other hand, the coefficient of thermal expansion of composites was measured at temperature up to 400 °C. It was found that the uniform introduction of silicon carbide fiber could significantly low the CTE of aluminum matrix composite, which could be attributed to the low CTE of SiC fiber and good fiber–matrix interface bonding. [ABSTRACT FROM AUTHOR]

• Microencapsulation of PCM with SiO 2 by Sol-gel process. • PCM@SiO2 incorporation effectively reduced concrete pavement surface temperatures, crucial for urban heat management. • Up to 30% PCM@SiO2 replacement maintained concrete strength within Indian standards, suitable for construction use. • Enhanced thermal energy storage capabilities were observed with increased PCM@SiO2 content. This study investigates the potential of enhancing thermal performance in pavement concrete by integrating microencapsulated phase change materials (PCM@SiO 2) using a Sol-gel process for encapsulation. With a concentration range from 0% to 20% in 5% increments, the effects of PCM@SiO 2 on both the mechanical strength and thermal performance of concrete were evaluated. Although the addition of PCM@SiO 2 resulted in a compromise in mechanical strength, significant improvements in thermal performance were observed, demonstrating a promising approach to mitigating temperature stresses and the urban heat island effect in pavement construction. This balance between mechanical and thermal properties underscores the potential of PCM incorporation as a strategic material choice for innovative urban development. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ polymerization of graphene-based polyamide 66 nanocomposites. • Strong enhancement in mechanical properties and thermal properties. • Synergistic effect of chemical and physical interfacial interactions. In this work, two types of graphene-based polyamide 66 (PA66) nanocomposites were prepared by in-situ polymerization. The effect of the surface functional groups of graphene oxide (GO) and the chemically modified GO (GO-DDA) on the structure and the properties of the nanocomposites were investigated. The nanocomposites achieved excellent enhancement in the properties. Compared to PA66/GO nanocomposites, PA66/GO-DDA nanocomposite showed higher Young's modulus, tensile strength and thermal decomposition temperature at all the filler content. For example, at the filler content of 0.3 wt%, PA66/GO-DDA nanocomposite exhibited 92 % increase in the Young's modulus, while PA66/GO nanocomposite exhibited 42 % increase. The thermal decomposition temperature was improved from 357 °C to 388 °C and to 383 °C by the incorporation of only 0.5 wt% of GO-DDA and GO, respectively. These results indicate the synergy reinforcement effect brought by the chemical interactions and the physical interactions between PA66 and GO-DDA. [ABSTRACT FROM AUTHOR]

In this study, we successfully applied an external magnetic field for the first time in preparing oriented steel fiber reinforced mullite castable (OSFRMC). The impact of the castable's rheology, duration of exposure to the magnetic field and strength of the magnetic field on the orientation of steel fibers and the properties of the refractory castable was investigated. When the duration of exposure to the magnetic field was set at 60 seconds and the strength of the magnetic field was 2.5 mT, an orientation index of steel fibers in the refractory castable of 0.96 was achieved. This specific castable contained 6 wt% of microsilica. Moreover, the castable with a high orientation index (0.96) of steel fibers exhibited significant improvement in mechanical strength and thermal shock resistance compared to the untreated castable. In order to investigate the fracture behavior of steel fiber-reinforced refractory castables with different fiber orientations, a comparative study was conducted using force-displacement curves and digital image correlation techniques. The primary factor behind this improvement is the directional alignment of steel fibers, which enhances the bridging effect and crack deflection toughness within the material. • Optimization of castables' rheology was a key step to prepare the castables. • The orientation of steel fiber had a great influence on the properties of castables. • Magnetic field was applied to prepare the castable with oriented steel fibers. [ABSTRACT FROM AUTHOR]

This work involves preparing zinc manganite nanoparticles (ZnMn 2 O 4 NPs) using the Sol-gel method. Polymer nanocomposites of polyvinyl alcohol (PVA)/Sodium alginate (NaAlg)- ZnMn 2 O 4 NPs were created using the solution casting technique. The polymer nanocomposites films were made with varying weight percentages of ZnMn 2 O 4 nanoparticles. With the addition of nanofiller, the reduced direct and indirect energy band gap values and increased Urbach energy values were discovered in the UV–Vis data. XRD data showed a reduction in crystallinity degree with dopant. ZnMn 2 O 4 NPs had a strong interaction with PVA/NaAlg blend, as confirmed by FTIR. The addition of ZnMn 2 O 4 NPs led to improved thermal stability of the polymer nanocomposites films. Additionally, the nanocomposites films' mechanical characteristics were examined. The loading of ZnMn 2 O 4 nanoparticles has been associated with an increasing trend in the mechanical properties of the nanocomposites, including its toughness, Young's modulus, Tensile strength (Ts), and elongation. The antibacterial activity of the nanocomposites against fungus and bacteria was studied. Additionally, PVA/NaAlg-ZnMn 2 O 4 nanocomposites films had good antibacterial characteristics against environmental microorganisms such as Gram-positive (G+) S. aureus and Gram-negative(G−) E. coli bacteria as well as fungi C. albicans and A. niger. It was observed that the biodegradability of the nanocomposite films was lower compared to the pure PVA/NaAlg film. Compared to pure film, the water solubility was decreased upon the addition of ZnMn 2 O 4 NPs. After ZnMn 2 O 4 was added to the pure blend, the WVTR decreased. The produced polymer nanocomposites films appear to be a promising material for food packing, according to these results. [ABSTRACT FROM AUTHOR]

Although many papers have been published in recent years regarding the effects of electrospinning (ES) on the properties of legume proteins (LPs), there has been no comprehensive review summarizing these findings, which was the main aim of this paper. Thus, the main purpose of this article was to review the properties of LP fiber-forming solutions as well as LP fibers through different characterization methods. Furthermore, the effect of encapsulating/incorporating different components into the ES solution of various LPs was studied. Cross-linking significantly improves the thermal stability, barrier properties, and insolubility of LP nanofibers. Also, Maillard-induced glycation leads to higher surface tension at the interface of oil-water contact, smaller emulsion droplets, and monomodal distributions. The ES quality of LPs varies depending on the viscosity, electrical conductivity, and surface tension of the protein solution; Specifically, too low and too high viscosity are detrimental due to the formation of beads and delay in Taylor cone formation, respectively; too low or too high conductivity will also cause insufficient jet elongation and significantly reduced jet stability, respectively. Insertion of nanoparticles improves the mechanical and thermal stability of LP nanofibers; however, the extent to which the incorporation meets safety regulations for adoption in food destinations remains a major challenge. [Display omitted] • The properties of legume protein fiber-forming solutions were reviewed. • Recent innovations in the electrospinning of legume proteins were introduced. • The role of electrospun legume proteins fibers in food packaging was explained. • The challenges in the electrospinning of legume proteins were described. [ABSTRACT FROM AUTHOR]

Geopolymer has excellent mechanical properties at elevated temperatures, but geopolymer concrete may not be so because of the large difference in thermal properties between geopolymer and aggregate which could lead to substantial thermal stresses when they are in a high temperature environment. In this paper we present an experimental investigation on the mechanical properties of GGBS-FA-SF blended geopolymer concrete with and without steel fibres at elevated temperatures. The influences of exposure temperature, coarse aggregate and steel fibre on the failure mode, compressive strength, elastic modulus, peak strain, and ductility of the geopolymer mortar and geopolymer concrete are examined. Based on the experimentally obtained data, empirical temperature-dependent stress-strain constitutive equations are also proposed, which can be used for the fire safety analysis and design of geopolymer concrete with and without steel fibres. [ABSTRACT FROM AUTHOR]

Mechanical properties and thermal conductivity are the key parameters for Mg alloys used as the structural components for heat dissipation, balancing good mechanical properties and high thermal conductivity is still a long-term challenge. Here, we investigated the influence of Y contents on the microstructure and mechanical properties of the as-cast Mg–4Al–4Zn–(4– x)RE– x Y (x : 0, 1, 2, 3, 4 wt%), where RE was the Ce-rich misch metal. Compared with Mg–4Al–4Zn–4RE alloy, the strength and ductility were significantly enhanced due to the well-optimized microstructure by the suitable substitution of Y for Ce-rich RE. Especially, the ultimate tensile strength and elongation were significantly improved from 201 MPa to 244 MPa and 8.0% to 16.8%, respectively, when the Y content was increased from 0 to 3.0 wt%. Meanwhile, the thermal conductivity still kept a high level within the range of 84.2–89.6 W(m·K)−1. The significantly improved elongation was mainly attributed to the reduction and refinement of coarse lamellar Al 11 RE 3 intermetallic phases with increasing Y contents. The as-cast Mg–4Al–4Zn–1RE–3Y alloy exhibited high performance with a combination of high tensile properties and good thermal conductivity. [Display omitted] • The substitution of Y for Ce-rich RE tailored microstructure and enhanced tensile properties of the as-cast AZE444 alloy. • The tensile strength and elongation were significantly improved by the suitable substitution. • The as-cast Mg–4Al–4Zn–(4– x)RE– x Y also possessed high thermal conductivity within range of 84.2–89.6 W(m·K)−1. [ABSTRACT FROM AUTHOR]

• SiC p /Al composites were prepared based on Fused Deposition Modelling (FDM) • Higher SiC volume fraction were obtained compared to other additive manufacturing methods. • complex-structure composites were prepared with excellent properties. SiC p /Al composites are widely used in space vehicles, electronic packaging, automobiles, rail vehicles and other fields due to their excellent mechanical and thermal properties. Complex-shaped SiC p /Al parts are usually manufactured by mechanical processing, which is expensive and time-consuming due to the high hardness of SiC phase. As a highly effective 3D molding method, Fused Deposition Modelling (FDM) of the complex-structure SiC p /Al composites was reported for the first time in this paper. SiC p /Al composites was densified by pressureless infiltration after FDM, and as-acquired bulk possessed high densification of 92.67 % and the SiC volume fraction of 43.2 %. Moreover, excellent performances were also presented, including flexural strength of 211 MPa, thermal conductivity of 112(W/m·K), and the thermal expansion coefficient of 8.67 × 10-6K−1. [ABSTRACT FROM AUTHOR]

Development of magnesium alloys with exceptional mechanical properties and high thermal conductivity is a prominent subject in the field of thermal conductive magnesium alloys. Rare-earth containing magnesium alloys are known for their ability to achieve higher strength. However, they often exhibit higher density and higher cost. This study developed a high-strength and high-conductivity magnesium alloy without the need for rare earth elements through considered composition design. By utilizing the pinning effect of Mg 2 Si and solute drag effects of Zn and Cu, a fine-grained magnesium alloy with an average grain size of merely 4.5 μm was achieved. The simultaneous introduction of hard Mg 2 Si particles and ductile Cu-rich particles allow Mg-1.38Si-0.5Zn-0.5Cu alloy (SZC100) to attain a desirable combination of strength and plasticity. Althogh free of rare-earth elements, this magnesium alloy demonstrates a thermal conductivity of 141.5 W/(m·K), a yield strength of 238 MPa, and an elongation of 16.2 %. [ABSTRACT FROM AUTHOR]

In this study, the microstructure, mechanical properties, and thermal conductivity of as-extruded Mg–4Zn-0.6Zr-xCa (x = 0, 0.3, 0.6, 0.9 wt%) alloys were investigated. The results revealed a bimodal grain size distribution in all the alloys due to incomplete dynamic recrystallization (DRX), characterized by the coexistence of elongated deformed grains and equiaxed DRX grains. The bimodal grain size distribution enhanced the mechanical properties of the studied alloys. Furthermore, Ca alloying facilitated the formation of Ca 2 Mg 6 Zn 3 phases, through which the DRX extent was also enhanced. The precipitation of secondary phases, along with the increased DRX induced by Ca addition, was beneficial in eliminating the lattice distortion of the alloys, resulting in improved thermal conductivity compared to the Ca-free Mg–4Zn-0.6Zr alloy. The optimum combination of mechanical properties and thermal conductivity was achieved in the Mg–4Zn-0.6Zr-0.6Ca alloy, with yielding strength, ultimate tensile strength, tensile fracture elongation, and thermal conductivity values of 271 MPa, 318 MPa, 17.6 %, and 123.9 W/(m‧K), respectively. This work demonstrates that Mg–Zn–Zr–Ca-based alloys can be developed with high strength and high thermal conductivity, significantly expanding the industrial application of magnesium alloys. [ABSTRACT FROM AUTHOR]

The molecular dynamics (MD) simulation method has been widely used to study mechanical and thermal properties of nanomaterials. However, a comprehensive review that compares the thermal and mechanical properties of carbon nanotubes (CNTs), boron nitride nanotubes (BNNTs) and their hybrid structures obtained using the MD simulation method is still lacking. In this paper, we review and document the contradictory results on the mechanical and thermal properties of CNTs and BNNTs published in the literature. We identify, a critical lack of discussion in the literature concerning the thermal and mechanical properties of BNNTs and the influence of encapsulated hydrogen on these properties. We hope that future work will address some of these contradictory data obtained using the MD simulations. We also anticipated that this work would provide important insights into the mechanical and thermal characterisations of these nanotubes for hydrogen storage and fuel cells applications. • A comprehensive survey of MD simulations of the mechanical and thermal properties. • High disagreement on the mechanical properties due to size, chirality, and defects. • Gaps in the study of mechanical and thermal properties identified. • The effects of encapsulated hydrogen in nanotubes require further investigation. [ABSTRACT FROM AUTHOR]

In view of the practical application of γ-AlON as a promising transparent structural ceramic, in-depth insight into its mechanical and thermal properties is essential. The solid-state MAS NMR technique was combined with XRD Rietveld refinement to confirm the crystal structure of Al (8+ x)/3 O 4- x N x (x = 0.299–0.575). These structural parameters were further applied to predict hardness and elastic properties based on theoretical exploration, which are in good agreement with the experimental values. A slight enhancement of mechanical properties with increasing nitrogen concentration is attributed to the stronger chemical bond in octahedra. The experimental thermal conductivity of γ-AlON transparent ceramics was improved slightly with the rise of x in the temperature range from 298 K to 1074 K. The intrinsic lattice thermal conductivity was determined by eliminating the extrinsic phonon scattering as well as the thermal radiation. The reason for the discrepancy between experimental and intrinsic thermal conductivity was revealed. The present methods provided powerful and accessible guidelines in optimizing the mechanical and thermal properties of oxynitride materials. [ABSTRACT FROM AUTHOR]

In this study, the influence of additional oxygen on the structural, mechanical, thermal, and corrosive properties of TiN coatings was investigated. A progressive change occurred in the structure from cubic TiN, Ti 0.50 O 0.11 N 0.39 , Ti 0.46 O 0.15 N 0.39 , and Ti 0.44 O 0.28 N 0.28 to mixed cubic and monoclinic Ti 0.39 O 0.40 N 0.21 , and finally to tetragonal TiO 2. Doping oxygen into TiN led to a significant change in hardness owing to the solid solution strengthening effect and the formation of ionic bonds and oxide phases. Ti 0.46 O 0.15 N 0.39 exhibited the highest hardness of ∼28.8 GPa. The addition of oxygen weakened the thermal stability of the TiN coating owing to the production of more oxides during annealing. After oxidation at 600 °C for 10 h, the Ti 0.50 O 0.11 N 0.39 coating with an oxide thickness of ∼0.86 μm exhibited an excellent oxidation resistance. The TiO 2 coating was not oxidized, thereby maintaining the initial morphology. In addition, the corrosion resistances of the TiON coatings were closely related to the oxygen content, where the low oxygen content compound Ti 0.50 O 0.11 N 0.39 exhibited the best corrosion resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

BaZrO 3 with the ABO 3 perovskite structure can be doped at the A or B sites to obtain the corresponding properties. In this study, BaZrO 3 was doped with Ca2+, Sr2+, Ti4+, and Ce4+. The structure, phase composition, and mechanical and thermal properties of the composites were investigated. The sintered Ba 1-x Ca x ZrO 3 samples with x = 0.2 and 0.4 exhibited relatively superior comprehensive behaviours; the cold modulus of rupture was increased by 127.36% and 134.59%, while that for BaZr 0 · 8 Ti 0 · 2 O 3 and BaZr 0 · 8 Ce 0 · 2 O 3 was increased by 99.30% and 112.37%, respectively. Further increases in strength and density were obtained in the Ba 0 · 8 Ca 0 · 2 Zr 0 · 8 Ti 0 · 2 O 3 and Ba 0 · 6 Ca 0 · 4 Zr 0 · 8 Ti 0 · 2 O 3 co-doped samples, and the corresponding apparent porosities were greatly decreased from 30.6% to below 1.0%. The thermal conductivities of the doped samples were generally low, achieving a minimum of 0.361 W/(m·K). The combination of high strength and low thermal conductivity demonstrate the significant application potential of BaZrO 3 -based composite materials. [ABSTRACT FROM AUTHOR]

SiAlON ceramics are primarily employed in ceramic cutting tools, which exploit their stable physical properties in high-temperature cutting environments due to their excellent mechanical properties. Here, Yb/Y-co-doped SiAlON ceramics are prepared by adding Yb and Y rare-earth (RE) ions in the RE x Si 12-(m + n) Al m + n O n N 16- n (m = 0.4, n = 1.0) composition. Yb 2 O 3 , the RE oxide, is the main sintering additive. For RE x composition design with (Yb 1- y + Y y) x , Yb 2 O 3 is replaced by Y 2 O 3 (y = 0.00, 0.25, 0.50, 0.75, 1.00). While Yb 2 O 3 has excellent high-temperature stability, it is limited by its microstructural characteristics, that is, the β-SiAlON morphology and limited fracture toughness due to the small cation sizes. Thus, the changes in the above properties are investigated for various Y 2 O 3 additive contents substituting for Yb 2 O 3. The average grain width decreases, and the equiaxed β-SiAlON grains are elongated with increasing Y 2 O 3 content. Regarding the mechanical properties, the hardness and fracture toughness are evaluated using the indentation fracture method. The hardness decreases with increasing Y 2 O 3 content; however, the fracture toughness exhibits a significant increase (∼53.6%) from 4.6 to 7.0 MPa⋅m1/2. Regarding crack propagation, intergranular fracture is mainly observed in the Yb/Y-co-doped SiAlON ceramics, whereas transgranular fracture is primarily observed in the Yb-single-doped SiAlON ceramic. Y 2 O 3 substitution increases the α/β-SiAlON phase ratio, and the grain boundary phase exhibits increasing vitrification with increasing Y 2 O 3 content. Moreover, the thermal properties of the Yb/Y-co-doped compositions are analyzed and discussed regarding intrinsic properties such as phonon scattering. The microstructural characteristics and improved fracture toughness derived from the Yb/Y-co-doped system designed in this study suggest considerable potential for the future composition design of ceramic cutting tools. [ABSTRACT FROM AUTHOR]

To provide the base data for the high-temperature processing of lunar regolith in future space activities, the materials prepared by fully melting of lunar regolith simulant (LRS) rather than the sintering is thoroughly characterized in terms of microstructure, thermophysical, and mechanical properties. The obtained material is glass–ceramic derived from the crystallization of molten regolith through a cooling process. Thermal expansion coefficient lies within a range of 6.42 × 10-6 1/℃ to 9.82℃ × 10-6 1/℃ between reference temperature (30 ℃) and softening point (919 ℃), and the thermal conductivity and specific heat capacity are close to the concrete. At room temperature, the ultimate compressive strength and the flexural strength is 67.1 ± 31.9 MPa and 100.7 ± 31.3 MPa, respectively, which are much higher than that of the traditional cement on Earth. Presented treatment crafts give a rise to thermal coating fabrication, and the products can be used as architectural and functional materials for the construction, operation, and maintenance of future lunar bases. [ABSTRACT FROM AUTHOR]

A series of (Ti 0.5 Nb 0.5)C-x wt.% SiC (x = 0, 5, 10, 20) composites were prepared by spark plasma sintering. Dense microstructures with well‐dispersed SiC particles were obtained for all composites. With the increment of SiC content, the Vickers hardness, Young's modulus and fracture toughness increase monotonically. An optimized flexural strength of 706 MPa was achieved in (Ti 0.5 Nb 0.5)C-5 wt.%SiC composite. (Ti 0.5 Nb 0.5)C-20 wt%SiC composite exhibits the highest fracture toughness of 6.8 MPa m1/2. The crack deflections and the suppression of grain growth were the main strengthening and toughening mechanisms. Besides, (Ti 0.5 Nb 0.5)C-20 wt%SiC composite exhibit the highest thermal conductivity of 45 W/m·K at 800 °C. [ABSTRACT FROM AUTHOR]

With the increasing demand for highly integrated circuits to optimize energy efficiency, reduce weight, and improve mechanical properties, finding a Magnesium (Mg) matrix material with excellent mechanical strength and high thermal conductivity poses a significant challenge. In this work, titanium (Ti) particles were introduced into AZ91 (Mg-9Al-1Zn) alloy to fabricate Ti/AZ91 composites, employing a combination of stir casting, extrusion and rolling processes. This strategy simultaneously enhances the mechanical properties and thermal conductivity of the Ti/AZ91 composites compared with AZ91 alloy. The incorporation of Ti particles serves to refine grains, expediting the formation of Mg 17 Al 12 phase within the Mg matrix. Optimal comprehensive mechanical properties are attained in 10 wt% Ti/AZ91 composite, exhibiting an ultimate tensile strength of 365 MPa, an elongation of 11.9 %, and a significantly low wear rate of 4.548×10−3 mm3/m. Notably, the 10 wt% Ti/AZ91 composite shows a 41.1 % reduction in wear rate relative to the AZ91 alloy, attributed to the incorporation of hard Ti particles. Furthermore, the thermal conductivity of the 2.5 wt% Ti/AZ91 composite exhibits a significant enhancement over that of the AZ91 alloy. Detailed discussions are provided on the fundamental mechanisms responsible for strengthening, wear resistance, and thermally conductive in Ti/AZ91 composites. These results highlight the substantial potential of Ti/AZ91 composites for lightweight structural applications, such as highly integrated circuits requiring excellent mechanical properties and high thermal conductivity. [Display omitted] • The 10Ti/AZ91 composite demonstrates a remarkable improvement in UTS, EL and wear resistance. • Enhanced mechanical properties results from the deformable Ti particles, refined grains, and weakening of texture. • The Ti/AZ91 composites possess exceptional thermal conductivity while maintaining high strength. [ABSTRACT FROM AUTHOR]

SiC is a promising structural material for future advanced nuclear energy systems. However, the inherent brittleness and difficulty of densification of SiC limits its practical application. In this study, medium entropy alloy (CrCoNi) reinforced silicon carbide composites (CCN/SiC) were sintered at 1950–2200°C by spark plasma sintering (SPS). The influence of CCN addition on the CCN/SiC composites was investigated in terms of microstructure, mechanical and thermal properties. The results show that SiC sintered at 2200℃ has the highest density, and the addition of 7.5 wt% CCN can significantly improve the fracture toughness of SiC. Transgranular fracture, crack deflection, and premature crack termination due to interfacial passivation are considered as potential toughening mechanisms. Although the addition of CCN can degrade the thermal conductivity of SiC ceramics, it has little effect on the structural stability of the SiC matrix at high temperatures. • A dimpled fracture feature was found in the CCN/SiC composites. • The composite exhibits very good structural stability at 1200 °C. • The addition of CrCoNi doubled the fracture toughness of SiC ceramics. [ABSTRACT FROM AUTHOR]

This paper examined the impact of graphene's different scales on carbon fibre-reinforced thermoplastic composites' thermal and mechanical properties (CFRTPs). Experiments using a mixing design method with graphene content of large, medium, and small scales as variables, thermal conductivity (λ) and mechanical properties (flexural (F), compression (C), and tensile strength (T)) as response values. The thermal-mechanical properties of multi-component composites were analyzed and modelled to improve them. Graphene with different scales could effectively bridge and enhance heat flow transfer along the graphene thermal conductivity network, significantly improving the composite's thermal conductivity. It was verified that the optimized composites exhibited excellent thermal conductivity (λ = 1.329 W/m·K), 140.3 % higher than that pure composite. Furthermore, the mechanical properties of the optimized composites saw significant enhancements, with flexural strength, compressive strength, and tensile strength increasing by 18.9 %, 22.8 %, and 13.2 %, respectively. Moreover, the optimized composite's thermal properties and energy storage modulus were also notably improved. [Display omitted] • Synergistic modification of CF/PPBESK composites using graphene at different scales. • Modelling of thermal conductivity and mechanical properties of composites was established. • Theoretical model fits well and predicts accurately. • Thermal conductivity and mechanical properties of composites improved significantly. [ABSTRACT FROM AUTHOR]

BaAl 2 Si 2 O 8 /BN (BAS/BN) ceramic composites were prepared using hot press sintering. The amorphous state of BAS ceramics exhibits a low melting point, high liquid-phase mobility, and good infiltration with BN grains, facilitating the sintering process. Conversely, the crystalline state of BAS has a high melting point and strength, contributing to the strengthening and toughening of the composite. The mechanical properties, thermal properties and thermal shock resistance of BAS/BN ceramic composite was investigated. Ceramic composites containing 40 vol% BAS have the best overall mechanical properties with bending strength, elastic modulus, fracture toughness, and hardness of 175 ± 3 MPa, 114.0 ± 1.2 GPa, 2.02 ± 0.10 MPa · m1/2, and 1.08 ± 0.01 GPa, respectively. The BAS/BN ceramic composite has excellent thermal shock resistance, and the residual bending strength shows a pattern of increasing and then decreasing with increasing thermal shock temperature difference. Finite element calculation results show that the cooling process is basically completed after 20 s of water quenching, the maximum thermal stress generated is about 22 MPa. [Display omitted] • The mechanical properties and thermal shock resistance of h -BN ceramics are enhanced by the introduction of BAS. • The main phases of BAS/BN ceramic composites are h -BN and h -BaAl 2 Si 2 O 8. • The thermal shock damage mechanism of BAS/BN ceramic composites is elucidated. [ABSTRACT FROM AUTHOR]

• Al 2 O 3 modified epoxy-glass fiber composites were successfully prepared and tested. • The composite material with 2 %Al 2 O 3 filler has the best comprehensive mechanical properties. • Thermal conductivity increased by 20%; the specific heat capacity is increased by 30%. • Burning time increased by 10 s. • The mechanical properties of the samples prepared by vacuum diversion process are better. The present study intends to use Al 2 O 3 as thermal conductivity filler, epoxy resin as matrix, and glass fiber as reinforcement material, and prepare Al 2 O 3 modified epoxy-glass fiber composite materials through vacuum diversion flow and hand paste molding. By changing the amount of Al 2 O 3 , performance tests and comparison are conducted. The results show that when the content of Al 2 O 3 filler is 2 %, the comprehensive mechanical properties are the best, the thermal conductivity is increased by about 20 %, the specific heat capacity is increased by about 30 %, and the combustion time is also increased by 10 s. [ABSTRACT FROM AUTHOR]

In this study, a novel bio-based composite of starch/plant fiber foaming tableware material was prepared by the hot-pressing foaming method. The influence of the content of carboxymethyl cellulos (CMC) as a new type of film-forming agent filler on the properties of foam materials was systematically investigated. The results showed that the foam material with 10 wt% CMC had excellent cell morphology and uniform cell size (the average cell size reached the minimum value of 465.7 μm), relatively high porosity (57.01%), and excellent thermal insulation properties (thermal conductivity: 0.0541 W/m·K). The tensile strength of foam increased from 4.289 MPa for 0 wt% CMC to 5.714 MPa for 10 wt% CMC loading. Similarly, the flexural strength also increased from 11.609 MPa to 15.719 MPa for the foam material with 10 wt% CMC. The thermal stability and viscoelastic properties of the foam material reached the highest after adding 10 wt% CMC. In addition, the increase of CMC content is beneficial to improve the oil resistance and biodegradability of the material. The research shows that CMC is an effective filler to improve the properties of starch/plant fiber foaming tableware materials, which can greatly promote the development of bio-based polymer foam materials. [Display omitted] • Starch/plant fiber foaming tableware material was prepared via a simple hot-pressing foaming method. • CMC was used as film-forming agent to optimize the properties of foam materials. • The addition of an appropriate amount of CMC (10 wt%) makes the cell size smaller and the cell structure more uniform. • CMC can improve the mechanical properties, thermal stability, viscoelasticity and thermal insulation of foam materials. • This new type of foam tableware material can be completely biodegradable under natural conditions within 21 days. [ABSTRACT FROM AUTHOR]

The current work presents a theoretical study of the physical properties of several FePt 2 ordered structures through first-principles calculations, including structural, magnetic, electronic, mechanical, phonon and thermal properties. The structural stabilities are certified by the enthalpies of formation, elastic constants, and phonon dispersion relationships. The tetragonal I 4/ mmm structure is energetically favorable compared to other types FePt 2 structures including Cmcm , Immm , P 6 3 / mmc and P 4/ nmm structures. The electronic density of states and the contributions of each d -orbital electron to the magnetic moment are analyzed to understand their magnetism. The bulk modulus B values of these FePt 2 structures are similar, but the Young's modulus E and shear modulus G as well as the elastic anisotropy are quite different. The thermal properties at finite temperature are estimated by the quasi-harmonic approximation. The I 4/ mmm structure has higher isothermal bulk modulus, lower thermal expansion coefficient and weaker thermal expansion anisotropy, which is more suitable for high temperature applications than other structures. Also, the sequence of thermal expansion anisotropy is P 4/ nmm > Immm > Cmcm > I 4/ mmm (≈ P 6 3 / mmc). [ABSTRACT FROM AUTHOR]

• Substitution of OPC cement with geopolymer for wood wool boards. • Formulate precursor and activator compositions in geopolymer and fibre treatment. • Light composite, low thermal conductivity, and meet minimum strength requirements. • Natural fibres influences the optimal Na 2 O concentration and modulus for strength. • Treated fibres recommended for higher modulus applications and improved strengths. This study investigates the substitution of ordinary Portland cement (OPC) with geopolymer in the production of wood wool geopolymer boards (WWGB), offering insights into manufacturing methods, design parameters, and performance characteristics. The composite formulation involves fibre pre-treatment, adjustment of precursor components, and control of activator compositions. The optimized formulation results in a lightweight composite with a density of 392 kg m−3 and porosity of 76 %, meeting prescribed minimum compressive (20 kPa) and bending strength (1700 kPa) requirements. The inclusion of natural fibres influences the optimal Na 2 O concentration and modulus for strength, with treated fibres recommended for higher modulus applications and improved strengths. Furthermore, it exhibits low thermal conductivity at 77 mW m−1 K−1, minimal moisture sorption, and low vapour resistance, offering a sustainable alternative in the field of insulation materials. [Display omitted] [ABSTRACT FROM AUTHOR]

• Impacts of alkaline earth and zinc cations on performances in Al-rich aluminosilicate glasses were unraveled. • Ca2+, Sr2+, and Ba2+cations in peraluminous aluminosilicate glasses mainly act as balancers for charged AlO 4 tetrahedra. • Similarities and differences of roles acted by Mg2+ and Zn2+ cations in peraluminous aluminosilicate glasses were identified. Here, the substitution of divalent cations is used as a strategy to tune the thermal and mechanical properties of aluminosilicate glasses. Following the successive substitution of R in 7RO·14MgO·28Al 2 O 3 ·51SiO 2 glasses (R= Mg, Ca, Sr, Ba, Zn), the nonlinear evolution in performances occurs, including glass transition temperature (T g), thermal stability (Δ T), fragility index (m), hardness (H V), crack resistance (C R), elastic modulus (E and G), and Poisson's ratio (ν). Specifically, although similar in ionic radius, replacement of Mg with Zn in present glasses results in clear differences in properties, such as a drop of 26 K in T g , 5.9 GPa in E , 9.5 in m , and an enhancement of 11 K in Δ T. Based on Raman spectra, 27Al and 29Si NMR Spectra, we revealed the chemical and atomic-scale structural origin of the nonlinear evolution in performances following the substitution of divalent cations in peraluminous aluminosilicate glasses. [ABSTRACT FROM AUTHOR]

Carbide dispersion for reinforcement is an effective strategy to enhance the performance of tungsten (W). High-entropy carbides (HECs), when compared to conventional carbides, offer superior thermal stability, hardness, mechanical strength, creep resistance, and wear resistance. This study represents the first successful incorporation of (HfNbTaZr)C as a reinforcing phase into a W matrix, resulting in the formation of a W-HEC alloy. Compared to other carbides such as ZrC, HEC demonstrates improved coherency with the W matrix, resulting in a significant increase in plasticity and enhanced high-temperature stability. This innovative approach paves the way for alloy design in high-temperature applications such as nuclear fusion, providing fresh insights into the enhancement of mechanical properties and thermal stability. • A (HfNbTaZr)C HEC has been synthesized, for the first time, incorporated as a reinforcing phase into the W matrix. • The mismatch between HEC(200) and W(110) is 0.018, smaller than the W-ZrC alloy, indicating better coherence with the W matrix. • The W-HEC demonstrates outstanding plasticity at 600 °C, displaying total elongation of 33.0%, surpassing other W alloys. • The W-HEC hardness decreases is less than the W-ZrC after annealing at 1800 °C, demonstrating superior thermal stability. [ABSTRACT FROM AUTHOR]

This work reports on the synthesis, mechanical, and thermal properties of in situ AlN/Al-12Si composite through laser powder bed fusion (LPBF) by blending Al-12Si powder with 5 vol% nano-sized BN particles. Incorporating nano-BN particles results in (i) formation of thermally stable AlN phase, preventing Si diffusion and breakdown of cellular structure, (ii) improvement of compressive yield strength (CYS), and (iii) reduction in coefficients of thermal expansion (CTE) and thermal conductivity. In addition, compared to Al-12Si alloy, the composite exhibits grain refinement from 38.8 to 1.2 μm in size, and the alteration of columnar grains (Al-12Si) to equiaxed grains (AlN/Al-12Si). At annealing temperatures above 573 K, the CYS of the unadulterated Al-12Si alloy had a ∼ 2.1 times greater reduction (from 285 to 200 MPa) compared to that of the composites (from 301 to 260 MPa). The formation of the AlN phase mitigates the significant reduction in CYS. The CTE of Al-12Si and AlN/Al-12Si are 27.3 × 10−6 K−1 and 24.3 × 10−6 K−1 respectively. There is good agreement between the measured CYS results and the calculated strengthening mechanisms. This work offers both theoretical insights and experimental data to support the use of LPBF AlN/Al-12Si composite in low- and moderate-temperature applications. • Novel in situ AlN/Al-12Si composite is successfully fabricated by laser powder bed fusion. • AlN phase generate from the reaction between BN particle and Al-12Si during laser melting. • AlN/Al-12Si composites have a higher compressive yield strength and lower thermal conductivity. • AlN phase leads to the grain refinement, improving the compressive yield strength. • AlN phase mitigates the reduction in coefficients of thermal expansion at medium temperature. [ABSTRACT FROM AUTHOR]

This study introduced the synthesis of a novel phosphorus-containing ionic liquid flame retardant called DOPA-MZ, which was used to develop epoxy resin (EP) composites with transparency, exceptional mechanical properties, and flame retardancy. Results indicate that adding 3% DOPA-MZ to the EP composite increases the Limiting Oxygen Index (LOI) to 30.3%, achieving a UL-94 V-0 rating. Differential Scanning Calorimetry (DSC) tests showed that DOPA-MZ promotes curing reactions, significantly raising the EP composite's glass transition temperature (Tg). Additionally, compared to pure EP, EP/8% DOPA-MZ reduced total smoke production (TSP) and total heat release (THR) by 23.8% and 5.9%, respectively. Thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were employed to analyze the flame-retardant mechanisms. These analyses revealed that DOPA-MZ primarily inhibits flames in the gas phase and enhanced flame retardation in the condensed phase. Furthermore, DOPA-MZ contains tertiary amine groups, which participated in the curing reactions between epoxy resin and curing agents. This tightens the integration of DOPA-MZ molecules with the cross-linked network formed during the epoxy resin curing process, leading to a 22.0% increase in tensile strength and a 17.0% increase in bending strength in EP/3% DOPA-MZ composite materials. [Display omitted] • Synthesized ionic liquid DOPA-MZ through the neutralization reaction of DOPO-derived acid and 1-MZ. • DOPA-MZ flame retardant exhibits excellent compatibility with epoxy resin and accelerates epoxy resin curing. • DOPA-MZ significantly enhances the fire safety of EP with only 0.13 wt% of phosphorus. • EP composites enhances mechanical and thermal properties while maintaining transparency. [ABSTRACT FROM AUTHOR]

Invar 36 alloy manufactured via the laser powder bed fusion (LPBF) process have attracted interest for their excellent low expansion properties. The properties of Invar 36 alloy, particularly thermal expansion, are highly sensitive to variations in process parameters. However, the effect of process parameters on microstructure and properties has not been systematically studied. This study examines the microstructure, mechanical properties, and coefficient of thermal expansion (CTE) of Invar 36 alloy under various processing parameters with different volumetric energy densities (VED). The results demonstrate that VED variations significantly impact the microstructure, mechanical properties, and CTE. Increasing VED leads to larger grain size and higher high angle grain boundaries, while geometric dislocation density and Taylor factor do not exhibit a linear relationship. At 89.29 J/mm3 VED, the Invar 36 alloy displays the optimal yield strength (405.4 MPa), tensile strength (489.3 MPa), and elongation (43.3%). The CTE meets the ASTM F1684 standard for all specimens. Lower relative density corresponds to smaller CTE, with the lowest CTE achieved at VED of 41.67 J/mm3. Furthermore, the influence of porosity on CTE diminishes with rising temperature. This research opens up the possibility of process parameters optimization for improved CTE and mechanical properties in as-printed Invar parts. [ABSTRACT FROM AUTHOR]

Arundo donax L. is investigated in this study as a suitable reinforcing agent for PLA/PP waste blend 3D printing filament. To improve the compatibility of the fibre and polymer, the Arundo fibre was chemically modified using alkali and silane treatment. Untreated and treated fibres were extruded with Polymer blends before being 3D printed. Effect of chemical treatment on thermal, mechanical, and morphological properties of the composites was investigated. The tensile, Izod impact, and water absorption of the 3D printed specimens were also tested. The Alkali treated (ALK) and combination of alkali and silane treatment (SLN) composites displayed good results. Tensile strength and modulus of the materials increased, as well as their maintained stability in the Izod impact test, demonstrating that the incorporation of ArF did not result in a loss in performance. SEM examination supported these findings by confirming the creation of beneficial interfacial contacts between the matrix and fibre components, as demonstrated by the lack of void between the matrix and the fibre surface. Furthermore, the alkali treatment of the ArF resulted in a considerable reduction in water absorption inside the biocomposite, with a 64% reduction seen in ALK composite comparison to the untreated composite (Un). After the 43-day assessment period. • Arundo fiber was chemically treated and utilized as a filler for the PLA/PP blend. • DSC, TGA, and MFI tests were performed on the ArF/PLA/PP composites. • The 3D-printed ArF composites were analyzed using tensile and Izod impact tests. • The agents responsible for improving the strength of ArF composites are discussed. • Water absorption of the 3D printed PLA/PP/ArF samples is studied. [ABSTRACT FROM AUTHOR]

The development of non-toxic, glycidol-free chain extenders is essential for enabling the recycling and reuse of both bottle-grade PET (PET-B) and thermoform PET (PET-T) in the packaging industry without the need for separation, thereby addressing the health concerns associated with commercial glycidol-based extenders. Herein, two novel series of novel glycidol-free chain extenders for bottle-grade recycled polyethylene terephthalate (PET-B) and thermoform-grade PET (PET-T) blends are reported. Blends of PET-B with up to 20 wt% of PET-T were incorporated into novel epoxy acrylate chain extenders with terminal (PEAT-BA) and internal (PEAI-BA) epoxy groups. These chain extenders are glycidol-free and improve the mechanical, rheological, and thermal properties of the PET-B/PET-T blends, offering better performance enhancements than are provided by commercial chain extender Joncryl ADR (J). The results showed significant improvements in intrinsic viscosity and mechanical properties by around 10 and 15 %, respectively, without affecting thermal properties. These findings can play a role in enabling the recycling and re-use of PET-B and PET-T blends without requiring separation while offering glycidol-free solutions. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The material properties discount calculation method based on fiber distribution was proposed; • The node heat transfer judgment and coupling technique based on the fiber diameter was proposed; • The number of meshes required for composite modeling can be significantly reduced based on the MPDCM and NGTJCT; • The modulus, strengths, and thermal conductivities of 3D SCf/UHTCMCs were evaluated. Conducting precise and consistent research into the mechanical and thermal properties of 3D short fiber-reinforced ultra-high temperature ceramic matrix composites (SC f /UHTCMCs) is essential for the lightweight design optimization of structures operating under extreme loads. While the current use of one-dimensional elements to simplify fiber solids addresses the mesh quantity and quality issues stemming from the demand for periodic cell size, it fails to accurately predict the mechanical and thermal properties of SC f /UHTCMCs. This research developed material models featuring fiber volume fractions ranging from 0 to 15%, derived from statistical data on the aspect ratio distribution of short fibers. Addressing the unique characteristics of SC f /UHTCMCs, we proposed the Material Properties Discount Calculation Method (MPDCM), which leverages fiber distribution to calculate the mechanical properties and thermal conductivity of composite materials. Furthermore, we introduced the Node Heat Transfer Judgment and Coupling Technique (NGTJCT), rooted in fiber diameter, to address the issue of unrealistic heat transfer between fiber nodes and matrix nodes in numerical assessments. Utilizing both MPDCM and NGTJCT allows for a substantial reduction in the required mesh count for composite modeling, while adhering to the dimensional needs of periodic cells and facilitating rapid and precise numerical analysis of 3D short fiber-reinforced composites. The outcomes of this research have the potential to overcome the existing bottleneck in the numerical analysis of SC f /UHTCMCs, minimize the necessity for complex experimental procedures in material performance studies, and lay the groundwork for engineering optimization design. [ABSTRACT FROM AUTHOR]

High-strength thermal insulation mortar, with its excellent mechanical properties and thermal insulation performance, is commonly used in building structure insulation and reinforcement renovations. In this study, vitrified microbeads and expanded perlite (EP) were used as thermal insulation materials to create high-strength thermal insulation mortar. The effects of the replacement percentage of these materials (50%, 65%, 75%, and 80%) on the density, water absorption, porosity, compressive and flexural strength, and thermal conductivity of the mortar were studied. The results show that increased replacement percentages of vitrified microbead (EP) led to a decrease in the density of the mortar and an increase in the water absorption rate and porosity. Furthermore, when the replacement percentages were increased, the compressive and flexural strength and the thermal conductivity of the mortar were reduced. Comparative analysis of the pore structure of high-strength thermal insulation mortar using scanning electron microscopy and digital microscope revealed the influence of vitrified microbead (EP) on the internal pore structure of high-strength thermal insulation mortar. The influence coefficient (η s) of volume replacement percentage of insulation materials was introduced using the Hamilton and Crosser models. Furthermore, the prediction model of thermal conductivity of high-strength thermal insulation mortar was established under different volume replacement percentages of vitrified microbead (EP). The calculated values of the model matched well with the measured values, with the ratios of the calculated values of the model to the experimental ones ranging from 0.85 to 1.15. • The physical, mechanical, and thermal conductive properties of mortar are found to be influenced by the amount of insulation. • The prediction model of thermal conductivity of high-strength thermal insulation mortar is established. [ABSTRACT FROM AUTHOR]

Drawing inspiration from the robustness and resilience of spider silk, this study harnessed a combination of polydopamine (PDA), cellulose nanofibers (CNFs), polyvinyl alcohol (PVA), and aminated carbon nanotubes (CNTs) to create a synergistic network through hydrogen and covalent bonding on the surface of carbon fibers (CFs). This strategy significantly bolstered the interfacial properties of the resulting composites. The enhancements in flexural strength, flexural modulus, interlaminar shear strength (ILSS), tensile strength, and interfacial shear strength (IFSS) were measured at 47.8 %, 75.2 %, 54.3 %, 55.6 %, and 51.8 %, respectively. These improvements are attributed to the formation of robust covalent and hydrogen bonds among PDA, CNF, PVA, and aminated CNTs. Furthermore, the thermal conductivity of the CF composites saw a 59.7 % increase, owing to the CNFs and CNTs. These nanofillers are instrumental in forming an efficient thermal conductivity pathway within the resin matrix, which contributes to the improved thermal conductivity. This study introduces a straightforward, eco-friendly, and innovative approach for the production of high-performance CF composites. [Display omitted] [ABSTRACT FROM AUTHOR]

Enhancing the mechanical properties and thermal stability of phthalonitrile polymers by hybrid modification holds significant importance in broadening their thermal-structural applications within high-temperature environments. Herein, fumed silica nanoparticles were considered as modifiers for a class of phenolic-type phthalonitrile resin, i.e., PN75, and their effects on mechanical properties and thermal stability were explored. First, contact angle tests (CA) were employed to show that the PN75 melt had good wettability on hydrophilic fumed silica (FS) and poor wettability on hydrophobic fumed silica (RFS). FS had a relatively satisfactory dispersion within PN75, which was indicated by scanning electron microscope (SEM), followed by FS/PN75 nanocomposites were prepared by melt blending under vacuum, with maximum FS addition 3 wt% of PN75. Second, the flexural strength and modulus of nanocomposites were increased by 23.5% and 11.9%. Finally, thermal stability of the FS/PN75 was promoted from 21.6% to 25.6% in char residue at 800 °C in the air atmosphere by the thermogravimetric analysis (TGA), which was contributed by the high heat-resistance and the shielding effect of FS. This work would inspire in-depth studies on modification and design of phthalonitrile-based hybrid composites for extreme thermal environment. [Display omitted] • Hydrophilic fumed silica exhibited well wettability with phenolic-type phthalonitrile resin. • Vacuum melt blending was proven as an efficient process achieving well dispersion of fumed silica nanoparticles. • Addition of fumed silica into phthalonitrile polymers improved the flexural strength and the char residue. [ABSTRACT FROM AUTHOR]

In this study, the ground state physical properties of Hg-based chalcopyrite semiconductors, HgXN 2 (X = Si, Ge and Sn), are investigated using the density functional theory (DFT), which is based on full potential linearized augmented plane wave (FP-LAPW) method. The structural, electronic, optical, mechanical and thermal properties of the body-centered tetragonal (BTC) phase, HgXN 2 (X = Si, Ge and Sn), have been calculated using the modified Becke-Johnson exchange-correlation potential (TB-mBJ). The obtained lattice parameters and volume are in good agreement with the values reported earlier, indicating that the results are reliable and reproducible. The phase stability of the titled compounds is elaborately studied and it is confirmed that all are thermodynamically, dynamically and mechanically stable. The electronic band structure demonstrated a direct band gap of 1.70 eV, 0.99 eV, and 0.94 eV for the HgXN 2 (X = Si, Ge and Sn) compounds, respectively. Both HgGeN 2 and HgSnN 2 compounds have a notably lighter carrier effective mass, resulting in higher carrier mobility and conductivity than HgSiN 2. The order of the mechanical hardness is as follows: HgSiN 2 > HgGeN 2 > HgSnN 2. The studied materials are also anisotropic in mechanically and optically. All the title compounds exhibit ductile behavior. The charge density contour plots indicates the dominant covalent nature of the bonds in HgXN 2 (X = Si, Ge and Sn). All these compounds have a high absorption coefficient and low optical reflectivity in the visible light range. Due to the favorable band gap and high absorption coefficient, these compounds could be suitable for optoelectronic or photovoltaic device applications. Moreover, the thermal expansion coefficient, thermal conductivity, melting point and fracture toughness behavior have been calculated, which also showed promise for thermal barrier coating (TBC) applications. • A comprehensive theoretical study on HgXN 2 (X = Si, Ge and Sn) compounds using DFT calculations. • The compounds are thermodynamically, dynamically and mechanically stable. • The compounds are ductile and elastically and optically anisotropic in nature. • The electronic band gap is 1.70, 0.99, and 0.94 eV for the HgXN 2 (X = Si, Ge and Sn) compounds, respectively. • The compounds can be used as potential coating materials in some specific sectors. [ABSTRACT FROM AUTHOR]

• We provide correlations among structural, thermal, and mechanical properties of medical device polymers following gamma, X-ray, and electron beam irradiation. • For most of the polymers investigated, little to no variation in properties was observed among the various radiation sources at a given dose. • This study supports medical product polymer selection for sterilization radiation resistance in view of product design and function. Stemming from security threats and shortages in supply, a recent push has emerged to expand alternatives to radioisotope Cobalt-60 gamma radiation for sterilization of polymeric medical products, including electron beam (E-beam) and X-ray machine-based sources. However, before large-scale implementation, the effects of these non-isotope-based methods must be thoroughly investigated from several perspectives, involving their potential detrimental effects on the structural, thermal, and mechanical properties of polymers in medical devices. This paper investigates such effects in commonly used medical device polymers, including polypropylene homopolymer (PPH), polyolefin elastomer (POE), low-density polyethylene (LDPE), acrylonitrile butadiene styrene (ABS), and chlorobutyl rubber (CIIR). To connect radiation-driven changes in polymer structural and thermal properties and corresponding changes in mechanical properties, several characterization techniques were utilized, including gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). We found that the tensile strength of X-ray irradiated PPH, as well as X-ray, E-beam, and gamma irradiated CIIR decreases due to chain scission, which is corroborated by GPC and DMA. The GPC results of LDPE suggest chain scission, but interestingly without a corresponding decline in tensile strength. By comparison, POE and ABS appear to undergo further crosslinking with increasing irradiation dose, which generally strengthens them. Importantly, in the vast majority of the cases, there were small to no changes in properties upon changing radiation technologies (at a given dose), i.e., no radiation source dependence. However, in a few specific cases, radiation method dependencies did arise, for instance, in terms of the molecular weight of PPH being significantly increased upon X-ray irradiation, while the melting temperature, glass transition temperature, and elongation at break reduced compared to gamma. Overall, this study provides valuable insight into radiation-driven chemical and structural changes in polymers that produce changes in physical and functional properties. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a promising, sustainable alternative to conventional petroleum-based polymers, but its mechanical and thermal properties limit its applications. This study introduces bamboo powders (BP) and montmorillonite clay particles (MMT) into the PLA matrix to prepare novel bio-based polymer hybrid composites using a unique combination of weight percentages of BP and MMT without chemical solvents through a stir casting process under optimised input parameters followed by compression moulding. Polymer hybrid composites were fabricated with different weight combinations, and their mechanical, morphological, and thermal properties were analysed. Tensile, flexural, and impact tests were performed to examine the mechanical performance, while thermogravimetric analysis and differential scanning calorimetry were used to assess thermal stability and characteristics. Microscopy observations showed a strong interaction between the bamboo, clay, and PLA matrix. The results revealed that the maximum tensile strength and modulus increased by 26.1 % and 40.8 %, respectively, with 10 wt% BP and 4 wt% clay content. Impact strength increased by 48 % with 15 wt% BP and 4 wt% clay content. Moreover, the thermal decomposition temperature, glass transition temperature (T g), crystallisation temperature (T c), and melting temperature (T m) of the hybrid composites improved considerably with 10 wt% BP and 4 wt% clay content, increasing by 4 °C, 2 °C, and 8 °C, respectively. Based on the findings of this study, the controlled processing parameters were optimised to fabricate the bio-based composite with significantly improved mechanical and thermal properties. These properties make the composite suitable for various automotive and structural applications. [Display omitted] • Polymer hybrid composites made by stir casting without solvents show enhanced mechanical properties. • Good interaction has been identified between matrix and reinforcement. • Bamboo and clay particles enhanced the mechanical performance of the composite. • Clay particles influence the thermal stability of the composite. [ABSTRACT FROM AUTHOR]

A study of the thermal and mechanical properties, as well as the molecular chain orientation of sulfur-vulcanized hydrogenated nitrile-butadiene rubber (HNBR) with acrylonitrile (ACN) content of 34 and 36 wt% and different crosslink density is presented. The objective is to establish the relationships between structural changes during stretching and the tensile and elastic behavior of HNBR having different chain microstructure. The (vulcanized) HNBR samples are amorphous at room temperature with glass transition temperatures that increase with increasing ACN content and crosslink density. The samples do not exhibit strain-induced crystallization. Stretching at room temperature only induces orientation of the amorphous segments along the stretching direction, which contributes to improved tensile strength, strain-hardening, and toughness, while preserving excellent elastic recovery of the rubbers. Precise correlations are established between the degree of orientation of the amorphous chain and the deformation in the framework of the affine deformation model of rubber elasticity. [Display omitted] • The structure and physical properties of hydrogenated nitrile-butadiene rubbers are investigated. • The relationships between strain-induced orientation and tensile and elastomeric behavior are established. • The ultimate tensile strength of vulcanized samples is associated to the degree of orientation of the amorphous phase achieved at high deformations before breaking. • The amorphous phase orientation contributes to improved toughness, strain-hardening and excellent elastic recovery. [ABSTRACT FROM AUTHOR]

As an environmentally friendly material, alkali-activated fly ash-slag (AAFS) is considered as a promising alternative cement because of its excellent mechanical properties and thermal stability. Nevertheless, high temperature induced damage in AAFS can potentially bring serious risks for its practical applications. This paper presents a systematic experimental study on behaviour of AAFS paste subjected to elevated temperatures up to 800 °C in terms of microstructure as well as thermal and mechanical properties. Microstructural evolution was characterised by means of Rietveld-based quantitative X-ray diffraction (QXRD), backscattered scanning electron microscope (BSEM) and X-ray microcomputed tomography (XCT), while thermal and mechanical properties were evaluated from thermogravimetric analysis (TGA), thermal deformation and compressive and flexural strengths. Results indicate that the compressive strength of AAFS paste rises by 77.5 % at 200 °C, followed by a mitigation from 200 to 600 °C and a regain at 800 °C. Different phases in AAFS paste including unreacted particles, reaction products and pores took up 30 %, 67.7 % and 2.31 % at ambient temperature, and 4.95 %, 84.8 % and 10.3 % after exposure to 800 °C, respectively, suggesting the recrystallisation with the formation of nepheline and gehlenite. In addition, the relationships between microstructural characteristics including three-dimensional (3D) pore structure features and thermal and mechanical properties of AAFS paste at elevated temperatures were explored and discussed in depth to gain insights into the underlying degradation mechanisms including pore pressure build-up, thermal gradient and phase transformation. [ABSTRACT FROM AUTHOR]

In this study, Mo–SiBCN metal-ceramic composites with or without sintering additives of MgO, Al 2 O 3 , and SiO 2 were fabricated by hot-press sintering at 1800 °C/60 MPa/30 min to investigate their phase composition, microstructural evolution, mechanical properties, thermophysical properties and thermal shock resistance. With the increase in amorphous SiBCN, a competition of reaction products between Mo and SiBCN as Mo 3 Si → Mo 3 Si + Mo 5 Si 3 + MoSi 2 → Mo 4.8 Si 3 C 0.6 + Mo 5 Si 3 + MoSi 2 → Mo 4.8 Si 3 C 0.6 were detected. Meanwhile, the bulk density, elastic modulus and bending strength of the Mo–SiBCN composites gradually decrease with increasing SiBCN content, but their hardness first increases and subsequently decreases, reaching the highest value of 14.46 ± 0.43 GPa with 30 vol% SiBCN incorporation. Due to the oxide additives that promoted the sintering of composites, the bending strength and hardness of Mo–SiBCN composites with the additives increased 3–6 times. The residual bending strength of the Mo–SiBCN composites after thermal shock at 900 °C and 1600 °C decreased with increasing SiBCN content, while for the composites with 10–20 vol% SiBCN, the residual bending strength increased by 140–147%. [ABSTRACT FROM AUTHOR]

Transition metal carbides are candidates for high-temperature structural ceramics because of their high melting point, high hardness, and high strength. However, one challenge is overcoming their high intrinsic brittleness. In this study, we investigated a new class of (Fe, Mo, W) 6 C carbides, which have three Wyckoff positions for metallic atoms (16d, 32e, and 48f) and one Wyckoff position for carbon (16c). These different Wyckoff positions provide a great opportunity to optimize the mechanical properties by the partial replacement of atoms at each Wyckoff position to obtain high-entropy carbides. The current results show that the phonon spectra have no imaginary frequency when Fe occupies the 16d or 32e positions, but a soft mode is observed when Fe occupies 48f. (Fe, Mo, W) 6 C η carbides have a higher fracture toughness compared with those of M 3 C and MC carbides owing to their low carbon content (14.3 at.%). The mechanical anisotropy of (Fe, Mo, W) 6 C is weak, which is beneficial for increasing the damage tolerance. The thermal expansion coefficients of the (Fe, Mo, W) 6 C η carbides are predicted to be approximately (8.5–9.5) × 10−6 K−1 at 1400 K. [ABSTRACT FROM AUTHOR]

The growing demand for type IV hydrogen tanks with long life, lightweight, high hydrogen storage density characteristics has posed new issues for liners. The paper discusses the causes of liner failure in terms of hydrogen permeation, thermal instability, and mechanical damage, as well as a focused analysis of alternative material optimization strategies. Through a detailed investigation of aggregate state structures, formulations and processes, the principles of material modification, primarily inorganic functional filler/polymer filler filling composite and laminated orientation, and their enhancing effects are sorted out. Besides, the benefits and drawbacks of blow molding, injection and welding, and the rotating technique, which were employed by some manufacturers are contrasted in the article, for overcome the problematic molding of hollow plastic liners with metal BOSS structures. This text will be a valuable resource for material exploitation as well as efficient and reliable molding of various liners. • Improve hydrogen storage density and application range by material modification. • The failure modes of the plastic liner material are discussed. • Hydrogen barrier, mechanical and thermal properties modify measures were reviewed. • Molding methods for synthetic liners containing metal inserts are compared. • The recommendations for future liner materials design and molding are presented. [ABSTRACT FROM AUTHOR]

Poor properties of native cassava starch film such as low mechanical properties and high water uptake are the limitations of biodegradable starch films. Dual modification is an alternative way to improve the properties. Characteristics and properties of oxidized, crosslinked and dually modified starch films by hydrogen peroxide oxidation and glutaraldehyde crosslinking were examined. Sequence of the dual modification was also studied. All starch films were prepared by casting technique using glycerol plasticizer. The oxidation and crosslinking of modified starch were confirmed by carbonyl and carboxyl contents as well as degree of crosslinking. The lowest and highest molecular weights of the modified starch were observed for the oxidized starch and crosslinked starch, respectively. Moreover, swelling power and moisture absorption of dually modified starch films was clearly lower than those of singly modified films. Additionally, both good stiffness and extensibility was also obtained from the dually modified films especially for the crosslinked-oxidized film. Moreover, thermal property and biodegradability were also determined. [ABSTRACT FROM AUTHOR]

In this study, a high-entropy approach was employed to design a new single-phase A 2 B 2 O 7 oxide for thermal insulation applications. Multicomponent high-entropy oxides, containing up to seven different cations, were successfully synthesized in a single defective fluorite structure. We observed that the incorporation of the functional cation, Zn2+, effectively blocked the heat radiation phenomenon by reducing the photon mean free path, and further reduced the high-temperature thermal conductivity owing to the larger free carrier concentration originated from the large number of oxygen vacancies. Although a large concentration of Zn2+ caused a slight reduction in thermal expansion, this study suggests that functional cations can be easily incorporated; thus, expanding the material diversity beyond the typical doping levels to develop new thermal barrier materials. [ABSTRACT FROM AUTHOR]

CeO 2 and Sc 2 O 3 co-stabilized ZrO 2 ceramics have attracted much attention as potential thermal barrier coatings (TBCs) materials for applications above 1300 °C. In this study, a series of Sc 0.04 Ce x Zr 0.96-x O 1.98 (SCZ, x = 0.08, 0.10, 0.12, 0.16) ceramic materials were synthesized with the solid-state method and their phase stability, microstructures and thermo-physical properties were systemically investigated by x-ray diffraction (XRD), Raman spectra, field emission scanning electron microscopy (SEM), thermal dilatometer, laser flash apparatus (LFA), and Vickers hardness tester. The results showed that Sc 0.04 Ce 0.12 Zr 0.84 O 1.98 (4S12CZ) and Sc 0.04 Ce 0.16 Zr 0.80 O 1.98 (4S16CZ) ceramic materials still maintained stable tetragonal phase structure after 100 h high temperature treatment at 1500 °C. SCZ had a high thermal expansion coefficient (TEC), low thermal conductivity, and high fracture toughness. The TEC of the ceramics increased with CeO 2 addition because lattice energy reduced with increasing substitution of Zr4+ by bigger Ce4+ while thermal conductivity decreased due to the increase of lattice distortion. Compared with 4S12CZ, 4S16CZ exhibited a higher fracture toughness of 6.48 ± 0.04 MPa m1/2 and showed the better anti-sintering property. Besides, the thermal conductivity, TEC and thermal cycling lifetime of 4S16CZ were optimal. The comprehensive performance of 4S16CZ suggested it could be explored as a promising TBC material for high-temperature application. [ABSTRACT FROM AUTHOR]