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Hydrogel, as one of potential soft materials for articular cartilage, has encountered pressing obstacles, such as insufficient mechanical properties, poor lubrication, and easy to wear. To tackle these, we propose a strong yet slippery polyvinyl alcohol/chitosan (PVA/CS) hydrogel with dual-physically crosslinked networks by harnessing freeze-thawing, salting-out, annealing, and rehydration. High mechanical properties of PVA/CS hydrogel can be readily regulated by adjusting proportion of PVA/CS and annealing temperature. The optimized hydrogel exhibits high mechanical properties with tensile strength of ∼ 19 MPa at strain of 550%, compression strength of ∼ 11 MPa at small strain of 39%, and outstanding toughness and antifatigue owing to the robust physical interactions, including hydrogen bonds, crystallization, and ionic coordination. Moreover, the equilibrium hydrogel shows low friction coefficient of ∼ 0.05 against Al2O3 ball under the condition of 30 N, 1 Hz, with water as the tribological medium, which is close to the lubrication performance of native cartilage. And meanwhile, the proposed cartilage-like slippery hydrogel displays stable long-term lubrication performance for 1 × 105 reciprocating cycles without destructive wear and structure damage. It is therefore believed that the biocompatible cartilage-like slippery hydrogel opens innovative scenarios for developing cartilage-mimicking water-lubricated coating and biomedical implants with satisfactory load-bearing and lubrication performance. [ABSTRACT FROM AUTHOR]

Excessive sediment concentration in water can cause damage to prefabricated concrete channels. This study evaluates the impact of sediment‐laden water flow on the mass loss of concrete after abrasion, incorporating scanning electron microscope‐energy dispersive spectrometer (SEM‐EDS) and X‐ray diffraction (XRD) analyses to assess the effects of four steam‐curing parameters—delay time, heating rate, constant temperature duration, and steam curing temperature—on the abrasion resistance of concrete used in enterprise prefabricated water conveyance channels. The results indicate that the abrasion resistance of concrete for prefabricated channels improves gradually with increases in delay time and constant temperature duration. When the delay time exceeds 3 h and the constant temperature time exceeds 4 h, the concrete's abrasion resistance can reach more than 5 h(g/cm2)−1. Rapid heating rates and excessively high steam curing temperatures adversely affect the concrete's abrasion resistance. However, when the heating rate is controlled within 20°C/h and the steam curing temperature does not exceed 70°C, the concrete's abrasion resistance can achieve more than 5 h(g/cm2)−1. In compliance with the standard DL/T5201‐2021 requirements, it is recommended that concrete with high demands for abrasion resistance should preferentially select steam‐curing parameters within these ranges. [ABSTRACT FROM AUTHOR]

Forged products are widespread in the market and there is an immediate need to counter this growing menace. Anti-counterfeit techniques using fluorescent materials with covert features that appear hidden under daylight and display characteristic fluorescence upon specific source irradiation have gained popularity. Carbon dots (CDs) that can be prepared through facile synthesis from various raw materials are a class of fluorescent materials that provide tremendous opportunities to combat counterfeiting. This work focuses on the fabrication of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) derived CDs via the solvothermal approach and their subsequent purification using column chromatography. The fifth fraction obtained exhibited remarkable yellow emission (λem = 540 nm) with a high fluorescence quantum yield of 53.22% and a lifetime of 4 ns. The CDs appeared quasi-spherical during TEM imaging with an average diameter of 1–3 nm and appeared polycrystalline from the SAED pattern. The XPS and TEM-EDS results suggested carbon as the major element along with oxygen and nitrogen as the other heteroatoms. The water-based ecofriendly ink formulated using the CDs was printed on UV dull paper using the flexography technique. The print-proof paper samples appeared pale pink under daylight and fluorescent yellow upon 365 nm UV illumination. Moreover, the stability of the print was confirmed upon exposure to strong UV radiation cycles and abrasion resistance. Besides, the fluorescence emission remained unaltered even after 5 months of storage under room temperature conditions. The ink was used to print on PVC sheets and FBB boards with good stability against scuffing, suggesting its applicability in the packaging industry. The CDs could also serve as fluorescent markers for identifying post-consumer plastic packaging for a circular economy. [ABSTRACT FROM AUTHOR]

Highlights: A multiscale hierarchical structure design, integrating wrinkled MXene radar-infrared shielding layer and flexible Fe3O4@C/PDMS microwave absorption layer The assembled stealth devices realize a near-perfect stealth capability in both X-band (8-12 GHz) and long-wave infrared (8-14 µm) wavelength ranges. The optimal device demonstrates exceptional curved surface conformability, self-cleaning capability (contact angle ≈ 129°), and abrasion resistance (recovery time ≈ 5 s). Developing advanced stealth devices to cope with radar-infrared (IR) fusion detection and diverse application scenarios is increasingly demanded, which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration limitations. Here, we propose a multiscale hierarchical structure design, integrating wrinkled MXene IR shielding layer and flexible Fe3O4@C/PDMS microwave absorption layer. The top wrinkled MXene layer induces the intensive diffuse reflection effect, shielding IR radiation signals while allowing microwave to pass through. Meanwhile, the permeable microwaves are assimilated into the bottom Fe3O4@C/PDMS layer via strong magneto-electric synergy. Through theoretical and experimental optimization, the assembled stealth devices realize a near-perfect stealth capability in both X-band (8–12 GHz) and long-wave infrared (8–14 µm) wavelength ranges. Specifically, it delivers a radar cross-section reduction of − 20 dB m2, a large apparent temperature modulation range (ΔT = 70 °C), and a low average IR emissivity of 0.35. Additionally, the optimal device demonstrates exceptional curved surface conformability, self-cleaning capability (contact angle ≈ 129°), and abrasion resistance (recovery time ≈ 5 s). This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments. [ABSTRACT FROM AUTHOR]

Background: High-speed flow of clean water or water with sediment released from aging spillways may cause abrasion and cavitation on the concrete surface gradually. The occurrence of irregularities on the concrete surface can exacerbate the erosion problem. Which might jeopardize the safety of dams constantly, hence the rehabilitation efforts become urgent tasks in dam safety projects. Methods: This study employs a 3D Computational Fluid Dynamics (CFD) model to quantitatively analyze the cavitation risk on the aging concrete surface of the Chay 5 spillway in Ha Giang, Vietnam, under various operation scenarios. There are two standards used to measure cavitation: the cavitation index (σ) which indicates the danger due to the drop of pressure in rapid flow, and the new gasification index (β) which takes into consideration the formation and collapse of bubbles behind asperities. Results: Three extreme flood cases may not result in potential cavitation because both σ and β exceed critical thresholds. Regarding the six controlled gate scenarios with normal water level, the σ profiles are approximated 1,0 showing a low likelihood of cavitation damage while the β values are smaller than 0.8, indicating a considerable risk of cavitation. Besides, the opening height of 100 cm poses the greatest risk of creating severe cavitation erosion in the concave area and slope portion. The flip bucket experienced the most vulnerable cavitation when the opening height is 400 cm. In addition, an approach to spillway surface rehabilitation involving specialized mortars has been presented. Conclusion: For aging conveyance structure, gasification index (β) takes into account irregularities surface, providing a more comprehensive assessment of the likelihood of cavitation damage than cavitation index (σ). After rehabilitation with anti-shrinkage high abrasion resistance mortar, the entire spillway surface is smooth. This allows for reducing the cavitation risk and improvement of life service thereof. [ABSTRACT FROM AUTHOR]

Highlights The semi‐crystallinity, thermoplasticity, high toughness, and light weight of polyamide‐6 (PA6) when reinforced with carbon nanotubes (CNTs) provide outstanding physical properties to the nanocomposites by combining the physical properties of both components. The processing difficulties arising due to the high toughness and abrasion resistance of PA6 and the agglomeration of in‐house synthesized long‐length CNTs can be tackled by melt‐mixing the components inside a twin‐screw extruder with a back‐flow channel. The 0.1–7 parts per hundred ratios (phr) of CNTs reinforced PA6 composites were characterized for their viscoelastic properties through oscillatory rheometry and dynamic mechanical analysis (DMA) at fixed operating conditions. The outcomes showed continuous shiftings in storage and loss modulus values with increasing reinforcements along with a viscoelastic transition at 3 phr CNTs reinforcements observed in DMA. A 19°C rise in glass transition temperature (Tg) was observed in DMA with 0.1 phr CNTs reinforcement, which showed further improvements with increasing CNTs content. The interactions among PA6 and CNTs were further confirmed by X‐ray diffraction (XRD) and Raman spectroscopy curves. These nanocomposites promise mechanical applications in the equipments of automobiles, aerospace, defense, biomedical, bio‐sensors, etc. Viscoelastic properties study for CNTs/PA6 composites Uniform intermixing of CNTs within PA6 via extrusion with back‐flow channel Detailed analysis of rheometry and DMA of the composites CNTs‐PA6 interactions estimated from rising intensity peaks in Raman spectra and X‐ray diffraction (XRD) Potential candidates for components in automobiles, aircraft, biomedicals, and sports industry [ABSTRACT FROM AUTHOR]

Effects of thermoplastic polyurethane (TPU) types (Recycled (R) and Virgin (V)) composites with 15 wt% and 30 wt% oakwood flour addition were studied. Selected physical, mechanical, morphological, and thermal properties of resulting polymer composites were analyzed. Test samples were manufactured using injection molding, except that abrasion resistance specimens were manufactured using a compression molding process. The findings indicated that the types of TPU and filler contents played a significant role in the density and mechanical properties of the TPU test samples. The increased oak wood flour contents in both TPU types showed improvement in density, tensile modulus, hardness, flexural strength flexural modulus, dynamic impact strength, and yield strength of the composite while decreasing the elongation at break values. In addition, both TPU types and filler contents significantly affected the densities of VTPU and R-TPU. The TPUs type, filler content, and cycle-rpm affected Taber's abrasion resistance values. Weight loss, which increased with the number of cycles for the control samples, decreased with increasing wood flour content. This study aimed to provide an overview of the effect of the wood flour content in the manufacturing of thermoplastic-reinforced composites and to provide a basis for further research and development efforts. [ABSTRACT FROM AUTHOR]

Graphene was mixed with varnishes at different ratios and applied by spraying method on different cross-sections of various wood materials, and their wear and adhesion performances were determined. Graphene (0.25%, 0.50%, 1%); varnishes (water-based and polyurethane varnish) and wood materials (beech (Fagus orientalis Lipsky), chestnut (Castanea sativa Miller), yellow pine (Pinus sylvestris L.), and spruce (Picea orientalis (L.) Link.)) were used. Adhesion and abrasion tests were performed. A total of 480 test specimens were prepared, 5 specimens for each wood type, cross-sectional direction, graphene ratio, and varnish type for adhesion and abrasion tests. The adhesion of the samples was determined by ASTM D 4541-09E1 pull-off test and abrasion resistance was determined in accordance with ASTM 4060-10. The data obtained were statistically analyzed and the significance values within and between groups were determined. As a result, abrasion resistance and adhesion increased in graphene 2 (0.50%) in both varnish types. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) was added in different proportions as a filler to the mixture for the production of recycled rubber tiles in order to improve their existing properties. The mechanical properties of novel rubber tiles were analyzed in the context of abrasion resistance, maximum stress (TS), stress at break (TSb), deformation at break (Eb), and hardness. An optimal mixture composition was found comparing the obtained results of mechanical tests; successful improvement of abrasion by 22.1%, Eb by 10.46% and hardness by 17.65% was achieved. Finally, the characterization of the new rubber tile by SEM/EDS and FTIR analysis was carried out, along with the stability and environmental impact assessment based on the leaching test. The accelerated aging test was conducted using a solar simulator, after which the mechanical properties, SEM/EDS, FTIR, and leaching test were re-examined. The results after the accelerated aging test showed that tiles with the addition of TiO2 have better mechanical properties compared to the reference ones; TS improved by 85.71%, Eb by 75.53%, and hardness by 9.43%. Therefore, we concluded that TiO2 as a filler in interaction with rubber and polyurethane composites significantly contributed to the improvement of the existing rubber tile, and the achieved improvements are useful for the original application of these tiles, which is the protection from injuries on playgrounds and sports fields. Also, the improvement achieved extends the service life of this type of tile, which contributes to the quality of this type of material. [ABSTRACT FROM AUTHOR]

The objective of this experimental study was to investigate the impact of different earth precursors, partially substituted with ground-granulated blast furnace slag (GGBFS), at varying replacement levels of 0–25% with 5% increments, on abrasion resistance, SEM analysis, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) tests after 90 days and compressive strength with dry density test at 28 days curing age. The precursors derived from waste aluminosilicate sources, such as metakaolin (MK), pumice powder (PP), waste ceramic powder (C), and bentonite (B), were utilized to produce GPMs. A total of 21 different combinations from four distinct series were produced. Depending on the results, it was found that all earth materials used had a positive effect on all properties at various replacement ratios. After 28 days, the mix containing 5% B reached its maximum strength of 64.15 MPa. The maximum values for abrasion resistance and compressive strength were obtained when the replacement level was 10% for all precursors, except bentonite, which achieved the best results at a replacement level of 5%. At a 25% replacement level, pumice powder showed superior performance on all properties compared to other precursors. Furthermore, the impact of the replacement level and precursor types was statistically evaluated using the two-way analysis of variance (MINITAB-ANOVA) technique. The statistical study showed that all variables had a substantial impact on the characteristics of the geopolymer mortar. The proposed geopolymer materials possess inherent stability, making them viable and sustainable substitutes for conventional construction materials. [ABSTRACT FROM AUTHOR]

UHPC and UHPFRC are distinguished materials that are utilised either partially as an overlay on an existing pavement or completely as a thin wearing slab over a base course in pavements. However, their full-scale structural applications are limited because of the significant amount of shrinkage and higher cost as compared to conventional concrete. In this article, to reduce shrinkage, UHPC and UHPFRC are developed using appreciable amount of 10 mm (nominal size) coarse aggregate by adjusting the mix of pavement quality concrete (PQC). In addition, their mechanical properties, abrasion, and shrinkage strains have been analysed. Further, extensive fatigue analysis of UHPC and UHPFRC was performed with significant number of samples. The results showed that UHPC mix exhibited a compressive strength of 100.21 MPa, a flexural strength of 11.41 MPa, and an abrasion resistance of 8.02% after 28 days of curing. Furthermore, its shrinkage strain was around 1841.51 µmm/mm. Notably, enhancements in strength properties were observed upon introducing 2.5% steel fibers by binder volume to the UHPC designated as the UHPFRC mixture. The abrasion resistance, compressive, and flexural strength increased by 20.55%, 40.24%, and 58.52%, respectively as compared to UHPC. Furthermore, the shrinkage strain decreased significantly by 96.9% compared to the base UHPC mixture. At stress levels of 0.55–0.95, UHPC showed a 72–166% longer fatigue life than PQC, but the failure pattern is the same. After addition of fibers to UHPC, fatigue life increased by 443–146% at the same stress levels compared to UHPC without fibers. [ABSTRACT FROM AUTHOR]

The synthesis of Cu2O nanoparticles (NPs) through the reduction of copper hydroxide using ascorbic acid and then Cu2O NPs modified with triacetoxy(vinyl)silane (TVAS) (m-Cu2O) by solution method were achieved. FTIR analysis of the unmodified Cu2O NPs and m-Cu2O NPs revealed the presence of absorption characteristics corresponding to Cu–O–Si linkages in the FTIR spectra of m-Cu2O NPs, which is strong evidence that the Cu2O NPs have been successfully modified. The characteristics and properties of m-Cu2O NPs were determined and compared to those of the u-Cu2O NPs. The results indicated that the modification process had an insignificant effect on the crystal structure and morphology of Cu2O NPs. X-ray diffraction analysis indicated that the crystal grain size of m-Cu2O NPs slightly increased, measuring 41.04 nm compared to 38.36 nm for the u-Cu2O NPs, this change was minor. However, the m-Cu2O NPs demonstrated enhanced dispersion into acrylic emulsion polymer, resulting in improved abrasion resistance and thermal stability of the acrylic coating. In comparison with an acrylic coating filled with the u-Cu2O NPs, the coating filled with m-Cu2O NPs exhibited a 70% increase in abrasion resistance and better thermal stability. Importantly, the antibacterial performance against E. coli and S. aureus of acrylic coating filled with m-Cu2O NPs was similar to that of the u-Cu2O NPs nanocomposite coating. These findings underscore the versatility and benefits of chemical modification in enhancing specific properties of the acrylic coating without compromising antibacterial efficacy. [ABSTRACT FROM AUTHOR]

This study addresses the increasing demand for eco-friendly rubber compounding additives by exploring greensynthesized zinc oxide (ZnO) nanoparticles. The green synthesis of ZnO nanoparticles is gaining attention due to its ecofriendly approach and potential applications. This study investigates the synthesis of ZnO nanoparticles using sweet lime peel extract as a green method, comparing it with chemical synthesis. The obtained nanoparticles are characterized and evaluated for suitability as activators in natural rubber composites for tire applications. Furthermore, the cytotoxicity of the prepared ZnO nanoparticles on mice cells is assessed, revealing lower toxicity for green-synthesized ZnO compared to chemically synthesized ZnO. Payne effect analysis on the composites demonstrates improved polymer-filler interaction and mechanical properties for the green-synthesized ZnO-loaded composites. Notably, the incorporation of green-synthesized ZnO leads to significant enhancements in tensile strength due to its higher surface area. It achieves desirable magic triangle tire properties, including low rolling resistance, high wet traction, and high abrasion resistance. These findings highlight the promising potential of green ZnO as an environmentally friendly alternative to chemical ZnO in rubber compounding. [ABSTRACT FROM AUTHOR]

This paper describes development of multi-layer deposition of Ti6Al4V added with 5 at% of Cr, 5 at% of Ni, and 2.5 at% of each Cr and Ni by μ-plasma powder arc additive manufacturing process. It presents findings on their microstructure, porosity, evolution of phases, microhardness, tensile strength, ductility, fracture morphology, fracture toughness, and abrasion resistance. Phase evolution found that α/α'-Ti and β-Ti phases are formed in all the alloys, intermetallic phase Cr 2 Ti evolved in Ti6Al4V5Cr and Ti6Al4V2.5Cr2.5Ni alloys whereas intermetallic phase Ti 2 Ni is formed in Ti6Al4V5Ni alloy. Their microstructure revealed that addition of chromium and nickel refined grains of their α-Ti and β-Ti phases. Elemental composition of the evolved phases found that at% of chromium, nickel, and vanadium in β-Ti phase is more than the α-Ti phase of the developed alloys. It enhanced their ultimate tensile and yield strength, and microhardness but reduced ductility. It changed the fracture mode from ductile to a combination of ductile and brittle mode possessing large size dimples, micropores, and cleavage facets. It is due to solid solution strengthening, evolution of intermetallic phases Cr 2 Ti and Ti 2 Ni, and grain refinement of β-Ti and α-Ti phases. Enhanced microhardness and presence of intermetallic phases improved fracture toughness and abrasion resistance of the developed alloys thus imparting them higher resistance to propagation of cracks and abrasive wear. [Display omitted] • Addition of Cr and Ni to Ti6Al4V alloy increased yield and ultimate tensile strength but reduced ductility. • The additional elements increased fracture toughness, microhardness, abrasion resistance. • The additional elements changed fracture mode to ductile and brittle with micropores and cleavage facets. • The additional elements refined grains of α-Ti and β-Ti phases. • β-Ti phase of Ti6Al4VxCryNi alloy has more at% of Cr, Ni and V than their α-Ti phase. [ABSTRACT FROM AUTHOR]

Fish skin leather is a sustainable alternative to traditional leather production. The goal of this study is to create a recipe for turning raw stingray leather into protective gloves for hands. The process flow of Stingray Leather Processing and optimization of each single step has been done. The technique is based on tanning agents, formulating new processing methods, conducting an extensive market analysis, and examining the environmental impact. The processed stingray leather was evaluated for resistance to abrasion, cur, and puncture resistance, and it was found that the stingray skin gloves showed better cut and abrasion resistance than the conventional gloves available in the market. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of fly ash and steel fiber on the abrasion resistance of ultra-high performance concrete (UHPC), this paper performed macroscopic mechanical test, underwater abrasion resistance test and microscopic characterization such as SEM and MIP to investigate the effects of fly ash and steel fiber on the workability, mechanical properties, microstructure, and abrasion resistance of UHPC. The results show that the replacement of cement by fly ash delays the emergence of hydration peak by about 3 h, and the cumulative heat flow at 3 d is reduced by 18%, significantly improving the workability of UHPC. The incorporation of fly ash reduces the mechanical properties of UHPC in the early stage and has no effect on the mechanical properties in the later stage. The incorporation of steel fiber improves the flexural strength and compressive strength of UHPC. The flexural strength and compressive strength are increased by 82% and 47% respectively due to the composite mixing of steel fiber and fly ash under steam curing. The addition of fly ash has little effect on the abrasion resistance of UHPC, while the addition of steel fiber improves the abrasion resistance of UHPC, and the composite mixing of steel fiber and fly ash increases the abrasion resistance of UHPC by 58%. The compressive strength and abrasion resistance strength of UHPC show a significant positive correlation. The incorporation of fly ash reduces the most available pore size, porosity and capillary pore content, making the internal structure of matrix more uniform and denser. [ABSTRACT FROM AUTHOR]

In this study, multiwalled carbon nanotubes (MWCNTs) were incorporated into vulcanized natural rubber (VNR) matrixes to create nanocomposites with improved mechanical, thermal, and electrical properties. The interfacial interaction of the MWCNTs with the VNR matrix was quantitatively evaluated based on the crosslink density value calculated using the Flory–Rehner methodology. Various rheometric parameters were influenced by the addition of the MWCNTs, including minimum torque (ML), maximum torque (MH), and scorch time (tS1). The MWCNTs significantly enhanced the vulcanization of the composites based on the VNR matrix. This study highlights the impact of MWCNTs on crosslink density, improving mechanical properties and reducing swelling in the VNR matrix. We discovered that the MWCNTs and the VNR matrix interact strongly, which improved the mechanical properties of the matrix. The MWCNTs improved the hardness, tensile strength, and abrasion resistance of the VNR/MWCNT nanocomposites. Based on dynamic mechanical analysis, MWCNT incorporation improved stiffness as indicated by a change in storage modulus and glass transition temperatures. The addition of MWCNTs to the VNR/MWCNT nanocomposites significantly improved their electrical properties, reaching a percolation threshold where conductive pathways were formed, enhancing their overall conductivity. Overall, this study demonstrates the versatility and functionality of VNR/MWCNT nanocomposites for a variety of applications, including sensors, electromagnetic shielding, and antistatic blankets. [ABSTRACT FROM AUTHOR]

Cotton is the most widely used natural cellulosic polymer and polyester is a synthetic polymer. The use of polyester fiber is increasing gradually day by day due to its strength and longevity, while the use of cotton fiber is decreasing due to its unavailability. At present, the use of cotton‐polyester composites is ubiquitous. This research work aims to assess the physical, mechanical and comfort properties of the woven fabric using cotton‐polyester composite yarns in a weft direction and coarser yarn count because of the use of these fabrics in the future for the denim manufacturing process. Four different samples were fabricated by using 100% cotton (10 Ne) yarn in the warp direction and 100% cotton, cotton‐polyester composite, and 100% polyester yarn in the weft direction of the fabric. Similar fabric and machine parameters were maintained for manufacturing all the samples. The samples were then tested for areal density, tensile strength, thickness, abrasion resistance and pilling, drape, flexural rigidity, and air permeability to find the optimum capability of the fabric. Physico‐mechanical properties with the proportion of increasing polyester components in fabrics improves areal density (184 to 199 g/m2), strength (almost 19 times in weft direction), drape (0.655% to 0.789%), and flexural rigidity (almost double). On the other hand, increasing comfortability properties with the proportion of cotton components in fabrics improve air permeability (139.85 to 159.58 cc/s/cm2), abrasion (only 3.036% mass loss), and pilling resistance (grading 4 after 2000 cycles). Highlights: Composite yarns made of cotton and polyester provide a method of improving fabric properties for better performance.Higher proportions of cotton make clothes more breathable and less likely to pill and wear out.Polyester parts make fabrics stronger, more durable, and less likely to wear out.Cotton‐polyester composites are ideal and have potential for various textile applications.Blending natural and synthetic fibers composite allows for customized fabrics that meet specific performance needs without compromising comfort. [ABSTRACT FROM AUTHOR]

Ground Granulated Blast Furnace Slag (GGBS) is an effective supplementary cementitious material because of its pozzolanic properties and positive environmental impact. This research explores the flexural strength of concrete pavements by analyzing several high-volume formulations of GGBS concrete against conventional mixes. The study aims to assess the viability of incorporating high-volume GGBS mixes in pavement construction, with a particular emphasis on their flexural performance. The study employs various GGBS content levels (60%, 65%, 70%, and 75%) in concrete mixes, with the control mix containing ordinary Portland cement. Specimens are prepared according to standard procedures, and flexural testing is conducted to evaluate their performance. Statistical analysis is performed to compare the flexural strength and behavior of GGBS mixes with the control mix. The results obtained from the experiments revealed that the GGBS concrete mixes had better flexural performance than the control mix, with more strength and less cost. The results provide the performance of large-volume GGBS concrete mixes under flexural loading circumstances, which helps to understand whether these mixes are suitable for use in concrete pavements. Ultimately, this research sheds light on the possibilities of utilizing large- volume GGBS concrete mixes as long-term substitutes for traditional concrete pavements, which may help in the promotion of greener and more long-lasting infrastructure solutions. [ABSTRACT FROM AUTHOR]

Babbitt alloy is a bearing material with excellent properties, including good anti-friction wear resistance, embeddedness, corrosion, and compliance, as well as sufficient bearing capacity. However, with the development of engines to have high speed and heavy load, the use of Babbitt alloy as a bearing material exposes its weaknesses of low bearing capacity, insufficient fatigue strength and a sharp decline in mechanical properties with an increase in working temperature. Therefore, its application scope is gradually narrowed and subject to certain limitations. Improving the tensile strength and wear resistance of tin-based Babbitt alloy is of great significance to expanding its application. In this study, tin-based Babbitt alloy was taken as the main research object; the particle size, microstructure, mechanical properties, and friction were systematically studied after the single addition of Y-Cu composite in tin-based Babbitt alloy liquid. The wear performance and the strengthening, toughening and wear mechanisms of tin-based Babbitt alloy were investigated under the action of Y in order to prepare a high-performance tin-based Babbitt alloy for bimetallic bearing. It was found that when rare-earth Y was added to the Babbitt alloy body, the wear properties were greatly improved. [ABSTRACT FROM AUTHOR]

Highlights Carbon black (CB) with different structural parameters together with graphene oxide were formed into uniformly dispersed filler network for enhancing the abrasion resistance of natural rubber/cis‐1,4‐polybutadiene rubber/trans‐1,4‐poly(isoprene‐butadiene) rubber blended composites. It showed that the CB structural parameters, such as specific surface area, surface activity and structural degree affected the formation of bound rubber. With the increase of bound rubber content, the homogeneity of filler network structure was improved and the filler‐rubber interaction was enhanced, resulting in a remarkable increase in the mechanical properties, thermal performance and abrasion resistance of the composites. Among the different types of CB, the composites filled with high‐structural‐degree CB of N134 had DIN wear volume as low as 76 mm3 and exhibited 19.5% higher abrasion resistance than N330. Wear surface observations and wear mechanism analyses showed that the increase in abrasion resistance was related to the improvement in tear resistance, hardness and thermal properties of the composites. Multiple linear regression analyses yielded that the structural degree in the structural parameters of CB had a significant correlation effect on the formation of bound rubber, and there was a strong linear relationship between the abrasion resistance of the composites and the content of bound rubber. Trans‐1,4‐poly(isoprene‐butadiene) rubber as compatibilizer for NR/BR blends. Synergistic enhancement of rubber using carbon black and graphene oxide. Carbon black with high structural degree promotes the formation of bound rubber. Described correlation between CB structural parameters and abrasion resistance of rubber. [ABSTRACT FROM AUTHOR]

The motivation behind this work is the preparation of polyurethane-magnesium aluminum layered double hydroxide (PU-LDH) nanocomposite and its application as a coating for steel protection. The coating was prepared with different doses of LDH, ranging from 0 to 2% of the coating weight. The effect of different concentrations on the mechanical, adhesion, and surface properties of PU coating is studied. Firstly, LDH was prepared via the coprecipitation process and then distributed in PU matrix. The nanocomposites were then crosslinked in the form of coating layers on steel. The preparation of the thermally stable crystalline LDH nanoparticles with 89 nm particle size was confirmed by FTIR, XRD, DLS, and TGA. SEM photos showed the dispersed and intercalated structure. The coating characteristics demonstrate that addition of LDH decreased the drying time and increased the dry film thickness of PU up to 1.5% due to the crosslinking between the large surface area nanofiller and polyurethane matrix. Furthermore, the prepared LDH nanofiller increased the adhesion strength, impact resistance, abrasion resistance, modulus, and flexibility of PU due to the strong polymeric network structure. The 2% nanocomposite coating shows poor properties due to the excess concentration and heterogeneous dispersion of nanoparticles within the PU polymer. The resistance to fire and some chemicals was supported by the thermally and physically stable LDH nanoclay. The former characterizations state that the proposed PU-LDH nanocomposite is an enhanced and applicable coating. [ABSTRACT FROM AUTHOR]

Highlights In this paper, the reasons for the improved wear resistance of irradiation‐modified Polytetrafluoroethylene (RM‐PTFE) and its composites above the melting point were investigated from the microcrystalline point of view by using methods such as crystallization kinetics, and it was found that the linear wear rate of RM‐PTFE was only 0.3 um/km, with a 1000 times increase in wear resistance, which was due to the transformation of its crystals from flake crystals that were easily dislodged to spherical crystals that were more resistant to abrasion. It was also found that the linear wear rate of Polytetrafluoroethylene (PTFE) with coke and graphite was 0.2 and 0.1 μm/km, respectively, and the abrasion resistance was further improved, which was attributed to the lowering of spherical crystal grain size by coke and graphite, which had better mechanical properties. These studies lay the foundation for future research on the frictional wear mechanism of RM‐PTFE above the melting point. Irradiation‐modified PTFE above the melting point Wear resistance of PTFE increases 1000 times Changes in crystal morphology dramatically increase wear resistance Use of crystallization kinetics to study the crystalline form of PTFE Small grain size improves wear resistance [ABSTRACT FROM AUTHOR]

To improve the interfacial bonding between hollow microspheres (RiM01) and natural rubber (NR), the silane coupling agents γ‐aminopropyltriethoxysilane (KH550) and γ‐methacryloyloxypropyltrimethoxysilane (KH570) are used in this study as intermediate reaction platforms for the modification of (RiM01) with glycidyl methacrylate (GMA), respectively. In the process, GMA reacts with KH550 and KH570 through epoxy group ring‐opening and free radical polymerization, respectively. Different NR/RiM01@GMA composites are prepared by a mechanical blending method. The results show that the addition of GMA improves the interfacial bonding between RiM01 and NR, and enhances the vulcanization rate and cross‐linking degree of the rubber composites. When KH550 is used as the reaction platform, the tensile strength of the rubber composites increases by 24% compared to composites with unmodified RiM01, while when KH570 is used, the tensile strength increases by 18%. Additionally, the tear strength and abrasion resistance of the rubber composites increase by 13% and 15%, respectively, when KH570 is used as the reaction platform. At the same time, the filler‐matrix interaction is strongest when KH570 is used as the reaction platform, and the rubber composites exhibit the lowest rolling resistance and the best resistance to heat and oxygen aging. Highlight: Modification of hollow microspheres by grafting GMA with KH550 and KH570, respectively.Improvement of rubber composite properties after modificationGMA improves the interfacial bonding between hollow microspheres and rubber. [ABSTRACT FROM AUTHOR]

This study addresses the global issue of recycling vehicle rubbish tires by a vacuum pyrolysis process, exploring a novel environmentally responsive approach for thermal decomposition and recovery of the carbon black particles contained in tires (25–30 wt%). Carbon black is typically used for its UV protection in plastics and abrasion resistance in composites and rubbers. This research aims at providing an eco‐responsible alternative to commercial carbon black of fossil origin by recycling the carbon black (rCB) from end‐of‐life tires. A particle reinforced composite material was developed containing rCB and high‐density polyethylene. For comparison purposes, an identical composite was manufactured using commercial carbon black (CB). Accelerated aging studies have been carried out on the materials. Topographic evolution of the samples with aging and oxidation kinetic of the surface and through the thickness were studied. Multiscale mechanical properties have been evaluated for a more comprehensive understanding of the mechanisms involved in the degradation. A comparison of the different materials properties was carried out in order to highlight the various elements linked to the degradation and UV protection of materials. This work helps demonstrating the feasibility of using recycled carbon black particles from waste tires as a high‐performance filler for plastics and composites. Highlights: Recycled carbon black (rCB) is an eco approach of revalorizing tire waste.Vacuum pyrolysis successfully allows recovery of reusable rCB.The rCB acts as a photon absorber, limiting degradation of HDPE.The rCB limits the cross‐linking responsible of embrittlement of HDPE.A critical carbonyl index of 20 marks the occurrence of cracks and degradation. [ABSTRACT FROM AUTHOR]

The recent emphasis on sustainability issues in construction materials has increased the interest to examine the effect of recycled aggregates on the performance of pervious concrete. This study investigated the effects of different types of recycled coarse brick aggregates (RCBAs), maximum RCBA size and using recycled fine brick aggregates (RFBAs) on the performance of pervious concrete. This has been done by testing void, density, compressive strength, splitting tensile strength, permeability, dust clogging and abrasion resistance. The quality of effluent passed through pervious concretes was also studied. According to the results, the usage of different types of RCBA decreased the compressive strength of pervious concrete, with the highest strength reduction of 55.3% which was obtained for 50% RCBA type A. A larger porous network of concretes by the incorporation of RCBA resulted in a higher permeability coefficient of up to 24.9%. Moreover, using RFBA in pervious concrete produces a much denser matrix and hence provides higher compressive and splitting tensile strengths and lower permeability coefficient. The permeability loss of pervious concretes due to dust clogging can also be decreased at 50% incorporation of different types of RCBA. Furthermore, results showed that RCBA types mainly influence the abrasion resistance of pervious concrete. Statement of Novelty: Different types of waste bricks may have different physical and mechanical properties which necessitated comprehensive experimental research about their performance in pervious concrete. To cover the gaps in this field, this research was conducted to investigate the effect of three major factors including (1) three different types of recycled coarse brick aggregates, (2) maximum aggregate size and (3) using recycled fine brick aggregates on the performance of pervious concrete. [ABSTRACT FROM AUTHOR]

This study explores the potential for recycling natural rubber (NR) latex waste from balloon production through the devulcanization and revulcanization processes. The mechanical devulcanization of colored latex balloon waste was conducted, followed by revulcanization using a sulfur-based system. The reclaimed rubber's properties, including crosslink density, tensile strength, and abrasion resistance, were compared with those of virgin NR. The results demonstrate that the reclaimed rubber maintains a crosslink density close to that of virgin NR. Hardness and abrasion resistance were comparable, indicating successful material recovery. Structural analyses, including FTIR and SEM microscopy, revealed that the devulcanization process effectively allowed for successful revulcanization. This study concludes that NR latex waste can be effectively recycled and reused in rubber composite formulations, offering a sustainable approach to waste management in the rubber industry and contributing to developing eco-friendly materials. In the context of this research, integrating advanced chemical and physical methods, such as solubility parameter calculations and enhanced devulcanization techniques, could further optimize the devulcanization process. These methods quantitatively enhance the efficiency of material recovery, offering a path to more sustainable recycling practices. The findings suggest that combining such advanced methodologies could significantly improve recycled NR latex's overall performance and applicability in industrial applications. [ABSTRACT FROM AUTHOR]

The focus of this study is to conduct pioneering research on utilizing poplar seed hair fibers in needle punched nonwovens. These fibers were blended with hollow PET fibers at two different weight ratios to obtain needle punched webs for the first time. The weight, thickness, abrasion resistance, bursting and tensile properties, hydrophobic/oleophilic surface characteristics of the nonwovens are analyzed elaborately. Finally, it has been demonstrated that poplar fiber-containing nonwovens have superior rose oil absorption compared to solely PET nonwoven fabrics. When compared the maximum adsorption capacities, the incorporation of 37.3 wt.% and 21.7 wt.% poplar fiber into PET nonwoven increased the oil absorption by approximately 35 and 24 times, respectively. Although pristine PET nonwoven was able to remove only 16% of MB dye from aqueous dye solution, addition of poplar fiber enhanced the removal process and the solution had been decolorized to nearly colorless. The results indicated that poplar blended nonwoven fabrics treated with NaClO2 show the high-performance removal of MB dye from wastewater, with the increased percentage of 40% and 67% for PET-PO30 and PET-PO60 fabric, respectively. Therefore, developing industrial scale surfaces with non-traditional and sustainable poplar seed fibers, marks a significant advancement for the textile industry. [ABSTRACT FROM AUTHOR]

Demographic growth and the need for housing remain significant issues. Compressed earth bricks (CEB) are appropriate materials due to their availability and thermal properties, but different considerations hinder their adoption. The influence of water on the mechanical properties and durability of CEBs stabilised with an alkali-activated geopolymer binder has yet to be thoroughly investigated. Thus, this study assessed the hydromechanical performance and durability of compressed earth bricks (CEBs) stabilised with an alkali-activated geopolymer binder. Dry mixes consisting of lateritic earth and 5—20% metakaolin (MK) binder, with respect to the dry mass of the earth, were prepared. A solution of NaOH at a concentration of 12 M was used to activate MK. The wet mixes were then statically compressed using a manual press at a stress of about 3.5 MPa. The dried CEBs were subjected to progressive mechanical characterisation after exposure to different water content and durability indicators assessment. A satisfactory mathematical correlation was established between the relative compressive strength and water content of the CEBs. CEBs stabilised with geopolymer binder showed increased stability to water, and their absorption capacity was relatively below the recommended 20% threshold. The abrasion resistance coefficient improved after the wetting–drying (W-D) cycles and was above the recommended 7 cm2/g. [ABSTRACT FROM AUTHOR]

Superhydrophobic nanocomposite coatings, prepared using adhesive and fillers, offer advantages including ease of fabrication and suitability for large-scale applications, but compared with other types of artificial superhydrophobic surfaces, poor durability still limits these surfaces from practical applications. The utilization of micro/nanoscale particles with both intrinsic hydrophobicity and robust mechanical properties to prepare coatings should significantly contribute to enhanced durability. Herein, rough and hydrophobic particles with micro/nano hierarchical structures were prepared at first, and robust superhydrophobic surfaces were fabricated using the prepared particles and additional nanoparticles. The initially prepared particles formed a rough framework of the coating, while additional nanoparticles provided inevitable nanoscale structures. A series of mechanical tests were carried out to validate the durability, and the surface with 20 wt.% NPs exhibited the best performance, withstanding 30 tape peeling tests, a 2.47 m sandpaper rubbing test (at a pressure of 5 kPa), the impact of 200 g of grit dropped from a height of 20 cm, and a 2 h acidic immersion. These appealing materials may attract attention for self-cleaning, high-speed water impact resistance, anti-icing, and anti-fouling applications in the coatings industry. [ABSTRACT FROM AUTHOR]

The Ni6035WC/WC-10Co-4Cr wear- and scour-resistant composite coating was fabricated using supersonic flame spraying technology. To further enhance the wear and scour resistance of the HVAF-sprayed Ni6035WC/WC-10Co-4Cr composite coatings, a post-treatment was conducted via vacuum remelting. This involved placing the coatings in a vacuum sintering process at 1120 °C for 10 min. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and hardness testing were employed to characterize the structure and morphology of the Ni6035WC/WC-10Co-4Cr coating, as well as to assess its wear and scour resistance. The results indicate that vacuum sintering significantly enhances the wear and scour resistance of the coating, while also improving its hardness, density, and bonding strength. The hardness of each coating after vacuum sintering, 1019 HV, 920 HV, and 897 HV, was improved by 6% compared to 966 HV, 906 HV, and 845 HV before sintering. The average wear rate of each coating after sintering was 13% lower than before vacuum sintering. Furthermore, the impact of varying WC-10Co-4Cr content on the coating's properties was examined under identical test conditions. It was found that the optimal overall performance was achieved with a WC-10Co-4Cr content of 20%, resulting in an average wear rate that was 19% lower than that of other coatings. [ABSTRACT FROM AUTHOR]

Effects of thermoplastic polyurethane (TPU) types (Recycled (R) and Virgin (V)) composites with 15 wt% and 30 wt% oakwood flour addition were studied. Selected physical, mechanical, morphological, and thermal properties of resulting polymer composites were analyzed. Test samples were manufactured using injection molding, except that abrasion resistance specimens were manufactured using a compression molding process. The findings indicated that the types of TPU and filler contents played a significant role in the density and mechanical properties of the TPU test samples. The increased oak wood flour contents in both TPU types showed improvement in density, tensile modulus, hardness, flexural strength flexural modulus, dynamic impact strength, and yield strength of the composite while decreasing the elongation at break values. In addition, both TPU types and filler contents significantly affected the densities of V-TPU and R-TPU. The TPUs type, filler content, and cycle-rpm affected Taber’s abrasion resistance values. Weight loss, which increased with the number of cycles for the control samples, decreased with increasing wood flour content. This study aimed to provide an overview of the effect of the wood flour content in the manufacturing of thermoplastic-reinforced composites and to provide a basis for further research and development efforts.

Abstract Cotton is the most widely used natural cellulosic polymer and polyester is a synthetic polymer. The use of polyester fiber is increasing gradually day by day due to its strength and longevity, while the use of cotton fiber is decreasing due to its unavailability. At present, the use of cotton‐polyester composites is ubiquitous. This research work aims to assess the physical, mechanical and comfort properties of the woven fabric using cotton‐polyester composite yarns in a weft direction and coarser yarn count because of the use of these fabrics in the future for the denim manufacturing process. Four different samples were fabricated by using 100% cotton (10 Ne) yarn in the warp direction and 100% cotton, cotton‐polyester composite, and 100% polyester yarn in the weft direction of the fabric. Similar fabric and machine parameters were maintained for manufacturing all the samples. The samples were then tested for areal density, tensile strength, thickness, abrasion resistance and pilling, drape, flexural rigidity, and air permeability to find the optimum capability of the fabric. Physico‐mechanical properties with the proportion of increasing polyester components in fabrics improves areal density (184 to 199 g/m2), strength (almost 19 times in weft direction), drape (0.655% to 0.789%), and flexural rigidity (almost double). On the other hand, increasing comfortability properties with the proportion of cotton components in fabrics improve air permeability (139.85 to 159.58 cc/s/cm2), abrasion (only 3.036% mass loss), and pilling resistance (grading 4 after 2000 cycles). Highlights Composite yarns made of cotton and polyester provide a method of improving fabric properties for better performance. Higher proportions of cotton make clothes more breathable and less likely to pill and wear out. Polyester parts make fabrics stronger, more durable, and less likely to wear out. Cotton‐polyester composites are ideal and have potential for various textile applications. Blending natural and synthetic fibers composite allows for customized fabrics that meet specific performance needs without compromising comfort.

Graphene was mixed with varnishes at different ratios and applied by spraying method on different cross-sections of various wood materials, and their wear and adhesion performances were determined. Graphene (0.25%, 0.50%, 1%); varnishes (water-based and polyurethane varnish) and wood materials (beech (Fagus orientalis Lipsky), chestnut (Castanea sativa Miller), yellow pine (Pinus sylvestris L.), and spruce (Picea orientalis (L.) Link.)) were used. Adhesion and abrasion tests were performed. A total of 480 test specimens were prepared, 5 specimens for each wood type, cross-sectional direction, graphene ratio, and varnish type for adhesion and abrasion tests. The adhesion of the samples was determined by ASTM D 4541-09E1 pull-off test and abrasion resistance was determined in accordance with ASTM 4060-10. The data obtained were statistically analyzed and the significance values within and between groups were determined. As a result, abrasion resistance and adhesion increased in graphene 2 (0.50%) in both varnish types.

The flame‐retardants aluminum diethylphosphinate (ADP) and aluminum hypophosphite (ALHP) were introduced into natural rubber (NR) and butadiene rubber (BR) to prepare composites. The effects of the two flame‐retardants on the processing characteristics, physical properties, flame resistance, mechanical properties and abrasion resistance of the composites were studied and compared. Results showed that both flame‐retardants delayed the vulcanization of the composites and increased the Mooney viscosity and ADP exhibited a more evident increase. Both ADP and ALHP improved the flame resistances of the composites, but the ADP improvement was more obvious, and the limiting oxygen index (LOI) of the composites increased from 22% to 28.5%, when ADP was added at 45 phr. The addition of ADP and ALHP reduced the rebound and increased hardness of the composites. The two flame‐retardants reduced the tensile strength, tensile elongation, and tear strength of the composites; both flame‐retardants adversely affect abrasion resistance, with abrasion loss of composite increased by 100% and 85% at 45 phr of ADP and ALHP, respectively. ADP can considerably improve LOI of the composites compared with ALHP, but it has a more significant negative impact on abrasion resistance. [ABSTRACT FROM AUTHOR]

Carbon black migration between ground tire rubber (GTR) and rubber matrix is essential in developing high-performance rubber/GTR composites. In this work, carbon black N220 (surface area: 107.1 m2/g, particle size: 20–25 nm) and N660 (surface area: 33.1 m2/g, particle size: 49–60 nm) were used as the reinforcement fillers for styrene-butadiene rubber (SBR) blended with reclaimed GTR. The combined effects of GTR devulcanization level and carbon black grade on the properties of SBR/GTR composites were investigated considering curing characteristics, thermal stability, physico-mechanical properties, dynamic mechanical properties, swelling behavior, and morphology. The results showed that, regardless of GTR devulcanization level and carbon black grade, application of GTR resulted in deterioration of mechanical properties compared to a reference sample without GTR. It was observed the reinforcement effect of carbon black in SBR/GTR composites was more visible with higher devulcanization level of GTR and lower particle sizes of carbon black fillers. SBR/GTR composites reinforced with carbon black N220 were characterized by tensile strength in the range of 15.3–16.3 MPa and abrasion resistance in the range of 120–123 mm3, which justify their potential application in the manufacturing of technical rubber goods or footwear. [ABSTRACT FROM AUTHOR]

Abstract Background Due to growing global concerns regarding the management of construction waste, this study investigates the feasibility of creating engineered geopolymer composites by replacing traditional industrial by-products (slag) with construction waste, specifically recycled brick waste powder. Results Polyvinyl alcohol fibers were incorporated into the engineered geopolymer composite mixtures. The substitution of slag with recycled brick waste powder was carried out at varying percentages: 0, 20, 40, 60, 80, and 100%, resulting in six different engineered geopolymer composite mixtures. The study evaluated the flexural strength, sorptivity, water absorption, and abrasion resistance of the engineered geopolymer composites, and also, microstructural characterization was conducted using scanning electron microscopy. The findings demonstrated that incorporating recycled brick waste powder into the engineered geopolymer composite mixes resulted in a decrease in flexural strength by 35.59% and a notable increase in midspan deflection by 339% when slag was replaced. Concurrently, there was a significant rise in water absorption and sorptivity by approximately 304 and 214%, respectively, when slag was entirely substituted with recycled brick waste powder. Conversely, abrasion resistance decreased, with the inclusion of recycled brick waste powder resulting in an 84% increase in volume change. The scanning electron microscopy (SEM) analysis showed active geopolymerization of recycled brick waste powder within the engineered geopolymer composite mixtures. Conclusions The results of this investigation demonstrate that it is feasible to produce engineered geopolymer composites using recycled brick waste powder instead of slag. The greater ductility and increased midspan deflection point to areas that require further optimization, even in spite of the observed decreases in flexural strength and abrasion resistance. The SEM examination reveals an active geopolymerization, highlighting the potential of recycled brick waste powder to produce environmentally friendly and sustainable construction materials. These results offer a good starting point for further studies that try to maximize the durability and performance of these composites.

At present, there are few research studies on the durability of microsurfacing. To further improve the service quality and durability of microsurfacing, five kinds of polymer‐modified emulsified asphalt were used to prepare microsurfacing mixture. Based on the mixing time, wet track abrasion test, and load wheel test, the composition rationality of the microsurfacing mixture was verified. The influence of different polymer‐modified emulsified asphalt on the water damage resistance, deformation resistance, and skid resistance of the microsurfacing was analyzed. The destructive effects of complex climatic conditions on the microsurfacing were simulated by means of damp heat aging, freeze‐thaw cycle, and xenon lamp light aging treatment. Taking the wear resistance and pull‐off properties after aging treatment and the change rate of various properties before and after treatment as evaluation indexes, the bonding durability of the microsurfacing was comprehensively evaluated by the ideal point method of entropy weight. The results show that the water damage resistance, abrasion resistance, and deformation resistance of the microsurfacing have a high correlation with the mechanical strength and adhesion performance of the modified emulsified asphalt binder. Xenon lamp aging has a significant impact on the bonding performance of the microsurfacing. Waterborne epoxy resin can effectively improve the bonding performance and bonding durability of the microsurfacing. Waterborne polyurethane can improve the freeze‐thaw resistance and xenon lamp aging resistance of the microsurfacing. [ABSTRACT FROM AUTHOR]

Nitriding is a cost-effective method to realize simultaneous improvements in tensile and fatigue properties and resistance to abrasion and corrosion. Previous studies reported that nitriding pure Fe enhances tensile strength by ~ 70% and fatigue limit by ~ 200%. It is due to the increase in surface hardness caused by the formation of γ′(Fe4N) and ε(Fe2-3N) nitrogen-containing intermetallic compound phases. However, the intermetallic compound layer is prone to brittle-like cracking. To better design nitrided steels, it is crucial to identify the crack growth mechanisms via analysis of the microstructural crack growth paths within the ~ 4–6 µm thick nitride layer. In the current work, we statistically evaluate the crack propagation behavior in the γ′ Fe4N layer during monotonic and cyclic tensile deformation in nitrided low-carbon steel (0.1 wt% C). Since nitriding typically results in the formation of columnar grains, the effect of morphology needs to be clarified. To this end, the steel was shot-peened and subsequently nitrided to promote equiaxed nitride grains morphology (~ 16% increase). Crack growth paths were comparatively evaluated for multiple cracks, and no significant effect of nitride morphology was observed. {100}γ′ is the predominant transgranular crack path in the monotonic tensile tested specimen, followed by {111}γ′. It is despite the elastic modulus of {111}γ′ < {100}γ′. This contrary behavior is explained by {100}γ′ plane having the lowest surface energy (density functional theory calculations). In the cyclic tensile loaded specimen, experiments revealed that transgranular cracking along {100}γ′ (cracking via symmetric dislocation emission) or {111}γ′ (slip plane cracking) is equally likely. [ABSTRACT FROM AUTHOR]

With the rapid development of the transport industry, there is a higher demand for environmental friendliness, durability, and stability of tires. Rubber composites with excellent mechanical properties, abrasion resistance, and low heat generation are very important for the preparation of green tires. In this study, the all-aqueous phase process was initially employed to prepare 2-Amino-5-mercapto-1,3,4-thiadiazole (AZT) functionalized graphene oxide (AGO). Subsequently, modified graphene oxide/silica/natural rubber (AGO/SiO2/NR) composites were obtained through latex blending and hot press vulcanization processes. This method was environmentally friendly and exhibited high modification efficiency. Benefiting from the good dispersion of AGO in the latex and the cross-linking reaction between AGO and NR, AGO/SiO2/NR composites with good dispersion and enhanced interfacial interaction were finally obtained. AGO/SiO2/NR composites showed significantly improved overall performance. Compared to GO/SiO2/NR composites, the tensile strength (28.1 MPa) and tear strength (75.3 N/mm) of the AGO/SiO2/NR composites were significantly increased, while the heat build-up value (10.4 °C) and DIN abrasion volume (74.9 mm3) were significantly reduced. In addition, the steady-state temperature field distribution inside the tire was visualized by ANSYS finite element simulation. The maximum temperature of the prepared AGO/SiO2/NR was reduced by 18.2% compared to that of the GO/SiO2/NR tires. This strategy is expected to provide a new approach for the development of low energy consumption, environmentally friendly, and long-life rubber for tires. [ABSTRACT FROM AUTHOR]

Untreated pyrolytic tire char was used in natural rubber (STR20) composites as single filler at loadings of 30–70 phr and co‐filler with carbon black (N330) at a total loading of 50 phr. The results were compared with rubbers filled with N330 and crumb rubber at 30 phr. The effects of fillers on cure characteristic, crosslink density, filler dispersion in natural rubber vulcanizates and their mechanical properties were investigated. The slight reversions were seen for the cure characteristics of 70 phr‐char‐filled and all co‐filler samples because the sulfur amount in the char together with the added sulfur could shift the vulcanization system from EV to SEV, whereas plateau cure curves were seen for the rest. While the highest tensile strength of char‐filled sample was obtained at 50 phr loading, whose tensile strength was about 88% of the N330 sample at 30 phr, 70‐phr‐char filled sample was superior in surface hardness, abrasion resistance and tear strength to N330 sample at 30 phr. For rubber with co‐fillers, the mechanical properties depended on the mass ratio of N330 to pyrolytic tire char. Therefore, it is possible to use untreated char as reinforcing filler for suitable applications according to their properties. [ABSTRACT FROM AUTHOR]

This work aims to fabricate the antibacterial coating with green biocide successfully. For this purpose, mimosa tannins were acylated with lauroyl chloride's aid and pyridine's support as a catalyst in the 1,4-dioxane, hexane and xylene solvents. Infrared analysis showed that mimosa tannins synthesized in the 1,4-dioxane were acylated better than in the other two solvents. FE-SEM analysis of the paint film showed that the acylated mimosa tannins at a content of 5 % dispersed quite well in the polymer matrix. The results of analyzing the mechanical properties of the paint film containing acylated mimosa tannins with contents ≤5 % show that the mechanical properties of the paint film are only slightly reduced compared to the mechanical properties of the pure coating, reaching the values: adhesion of size #1; abrasion resistance of 132.8 L/mil; impact strength of 170 kg cm and a relative hardness of 0.78. Antibacterial testing shows that the paint film containing 5 wt% acylated mimosa tannins have good antibacterial activity. [ABSTRACT FROM AUTHOR]

Ti6Al4V alloy has become the preferred material for key components in machinery due to its many excellent mechanical properties, however, the defects of Ti6Al4V alloy such as low hardness and poor wear resistance limit its wider application in the mechanical field. In view of this, the laser texture technology was used to prepare a streamlined symmetrical texture on the surface of Ti6Al4V alloy, and the effects of laser streamline texture with different parameters on the wear resistance of Ti6Al4V alloy material were studied by friction test system under oil lubrication conditions. SEM and LICHEN electronic balance equipment were used to characterize the wear scar morphology and wear amount on different sample surfaces. The experimental results show that when the texture length is 400 μm and the depth is 600 μm, the friction coefficient and wear of the sample are smaller, and the friction reduction effect is better. In addition, ANSYS Workbench software was used to simulate the flow characteristics of lubricating oil on the texture surface, and it was found that the decrease of friction coefficient in the experiment was mainly caused by the increase of oil film pressure caused by the change of flow velocity and flow direction of lubricating oil under the action of texture. The increase of oil film pressure can improve the bearing capacity of the oil film and effectively reduce the friction coefficient of the friction pair. [ABSTRACT FROM AUTHOR]

In recent years, laser cladding technology has been widely used in surface modification of titanium alloys. To improve the wear resistance of titanium alloys, ceramic-reinforced nickel-based composite coatings were prepared on a TC4 alloy substrateusing coaxial powder feeding laser cladding technology. Ti (C, N) ceramic was synthesized in situ by laser cladding by adding different contents (10%, 20%, 30%, and 40%) of TiN, pure Ti powder, graphite, and In625 powder. Thisestudy showed that small TiN particles were decomposed and directly formed the Ti (C, N) phase, while large TiN particles were not completely decomposed. The in situ synthetic TiCxN1−x phase was formed around the large TiN particles. With the increase in the proportion of powder addition, the wear volume of the coating shows a decreasing trend, and the wear resistance of the surface coating is improving. The friction coefficient of the sample with 40% TiN, pure Ti powder, and graphite powder is 0.829 times that of the substrate. The wear volume is 0.145 times that of the substrate. The reason for this is that with the increase in TiN, Ti, and graphite in the powder, there are more ceramic phases in the cladding layer, and the hard phases such as TiC, Ti(C, N) and Ti2Ni play the role in the structure of the "backbone", inhibit the damage caused by micro-cutting, and impede the movement of the tearing point of incision, so that the coating has a higher abrasion resistance. [ABSTRACT FROM AUTHOR]

In this paper, Ni was introduced into the matrix of carbon fiber reinforced SiOC (C/SiOC) composites by the precursor infiltration and pyrolysis method to catalyze the generation of in situ formed nanostructures including carbon nanotubes (CNTs), turbostratic carbon, and SiC. The effect of in situ formed nanostructures catalyzed by Ni on the properties of the C/SiOC composites was investigated. The results demonstrated that the presence of in situ formed nanostructures in the matrix improved the densification and mechanical properties of C/SiOC composites. In addition, the incorporation of in situ formed nanostructures facilitated the formation of thermal conductivity pathways within the composites, thereby enhancing the thermal conductivity of C/SiOC composites. Furthermore, in situ formed nanostructures‐containing C/SiOC composites developed a carbon friction layer comprising CNTs and turbostratic carbon, which significantly enhanced the abrasion resistance, endowing C/SiOC composites stable friction coefficients, and lower levels of wear. [ABSTRACT FROM AUTHOR]

The main motivation of this work is to use ceramic microspheres (CMs) as a potential filler in polyamide 6 (PA6) to enhance its mechanical and tribological performances. Polyamide 6 composites bearing CMs in different weight ratios (10%–40%) are processed by melt blending and characterized primarily by tensile and bending test, dynamical mechanical analysis, and ball-on-disc wear test. This work clearly shows that the addition of CMs gives rise to superior mechanical and wear resistance contribution to PA6. The tensile strength, tensile modulus, flexural strength, and flexural modulus of the composites are enhanced up to 11%, 25%, 37%, and 80%, respectively, over those of the pristine polymer. The wear resistance of 40 wt% CMs containing composite is 60% higher than that of pure PA6. Consequently, it has been found that CMs can be a suitable alternative especially in applications where mechanical strength is desired due to its advantages of high rigidity and sliding wear resistance. [ABSTRACT FROM AUTHOR]