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We characterized the tensile behavior of sclera, optic nerve (ON), and ON sheath in eyes from donors with glaucoma, for comparison with published data without glaucoma. Twelve freshly harvested eyes were obtained from donors with history of glaucoma, of average age 86 ± 7 (standard deviation) years. Rectangular samples were taken from anterior, equatorial, posterior, and peripapillary sclera, and ON sheath, while ON was in native form and measured using calipers. Under physiological temperature and humidity, tissues were preconditioned at 5% strain before loading at 0.1 mm/s. Force-displacement data were converted into engineering stress-strain curves fit by reduced polynomial hyperelastic models and analyzed by tangent moduli at 3% and 7% strain. Data were compared with an age-matched sample of 7 published control eyes. Optic atrophy was supported by significant reduction in ON cross section to 73% of normal in glaucomatous eyes. Glaucomatous was significantly stiffer than control in equatorial and peripapillary regions (P  0.997). Tangent moduli had variability similar to control in most regions, but was abnormally large in peripapillary sclera. Tensile properties were varied independently among various regions of the same eyes. Glaucomatous sclera is abnormally stiff, but the ON and sheath are abnormally compliant. These abnormalities correspond to properties predicted by finite element analysis to transfer potentially pathologic stress to the vulnerable disk and lamina cribrosa region during adduction eye movement.

Welded hollow spherical joints (WHSJs) are commonly used joints in grid structures, and their mechanical behavior under fire will directly affect the service life and safety behavior of grid structures. Therefore, the WHSJs were heated to the specified high temperature, and the tensile experiments were performed on non-stiffened WHSJs exposed to elevated temperatures. The failure modes, axial load–displacement curves, and mechanical behavior of the non-stiffened WHSJs exposed to elevated temperature were obtained. The experiment indicates that the failure mode of the axial tensile non-stiffened WHSJs is a pull-out failure. With the increase of heating temperature, the mechanical behavior of non-stiffened WHSJs gradually declines. The ductility of the non-stiffened WHSJs gradually increases with the heating temperature. Compared with the existing studies, the load-bearing capacity reduction trend of WHSJ exposed to elevated temperature is basically similar, and the stiffener has basically no function to improve the behavior of tensile WHSJs exposed to elevated temperature. The reliability of the numerical simulation was proved by comparison with experiments. According to the finite element analysis, the design method for the mechanical behavior of the non-stiffened WHSJs subjected to axial tension exposed to elevated temperature was proposed. [ABSTRACT FROM AUTHOR]

Stress relaxation is a time-dependent mechanical behavior of textile materials, which can affect the performance of the fabrics in various applications, especially technical applications such as tensile structures, geotextiles, and medical textiles. The present study aims to consider the effect of fabric structure (Tricot, Locknit, Satin, Queen’s cord, Reverse Locknit, and Sharkskin) on the tensile stress relaxation of biaxial warp-knitted fabrics. According to the results, the fabric structure remarkably influences its stress relaxation. The stress relaxation of the fabric in the course direction increases by increasing the length of underlaps in the front and back guide bars. Using elastic yarns as weft yarns in the fabric structure reduces the stress relaxation of the fabric in the course direction without affecting the fabric’s stress relaxation in the wale direction. Finally, to improve the functionality of pressure garments under stress relaxation, using elastic weft yarns in the fabric structure and bounding the warp and weft yarns in the biaxial warp-knitted fabrics by the Tricot structure is proposed. [ABSTRACT FROM AUTHOR]

This study compares dip brazing and TIG welding operations carried out under optimal conditions on the parameters of strength, deformation, and ability to resist shocks for Al-64430 joints, which find extensive use in automobile and telecommunication industries. The fabricated samples were tested for bump test, surface deformation, microhardness and tensile strength, and the joint properties were studied through SEM, EDAX mapping and EDX. Compared to the dip-brazed samples, the TIG welded samples achieved 161% greater strength and 1000% greater elongation but subsequently 1330% higher surface deformation. Both joints were able to pass the bump test; however, some degree of cracks were observed post testing in both samples. Both samples achieved similar joint microhardness values, but notably, compared with the TIG welded sample, the brazed sample showed no HAZ zones in terms of microhardness variation, where a substantial decrease in microhardness was recorded. This absence of the HAZ region was also confirmed through the microstructure. Both primary and secondary silicon were observed in brazed samples, which had finer grain sizes than did the welded samples. Dendrite formation was observed for the brazed samples, whereas a uniform distribution of aluminium was observed for the welded samples. Fractographic analysis revealed brittle intergranular fracture with small dimples present at the fracture point for the brazed joints, while out-of-plane fracture with sharp edges indicated a more ductile nature for welded joints. [ABSTRACT FROM AUTHOR]

Stainless steels have many practical applications requiring various mechanical or chemical demands in the working environment. By optimizing a device used in mechanical experiments for torsional loading, several cylindrical samples were tested (both ends twisted with the same torque value in opposite directions) of 316L stainless steel (SS) to evaluate changes in the structural, chemical, and mechanical characteristics. Initially, the experimental samples were pre-loaded by tension in the elastic range (6%) and then subjected to torsion (772°) at different rates: 5, 10, and 20 mm/min. The experimental sequence consisted of a combined loading protocol with an initial tensile test followed by a subsequent torsional test. Two reference tests were performed by fracturing the samples in both torsion and tension to determine the mechanical strength parameters. The macro- and microstructural evolution of the samples as a function of the torsional degree was followed by scanning electron microscopy. The microhardness modification of the material was observed because of the strain (the microhardness variation from the center of the disk sample to the edge was also monitored). Structurally, all samples showed grain size changes because of torsional/compressive deformation zones and an increase in the degree of grain boundary misorientation. From the tensile and torsional behaviors of 316L SS and the structural results obtained, it was concluded that these materials are suitable for complex stress states in the elasto-plastic range through tensile and torsion. A reduction in Young's modulus of up to four times the initial value at medium and high stress rates was observed when complex stresses were applied. [ABSTRACT FROM AUTHOR]

It has proven to be a difficult task to design and provide an ankle-foot orthosis (AFO) that enables the client to walk securely and comfortably without bearing weight through the lower leg and foot skeletal parts. Although it is widely acknowledged that the patella tendon weightbearing (PTB) ankle-loot orthosis only partially unweights the lower tibia, ankle, and foot, it is nevertheless frequently prescribed for this purpose. In this work, two ankle foot orthoses of the AFO PTB type of Calf-corset were manufactured using a vacuum molding technique based on two kinds of materials as composite material reinforcement. The first AFO material was based on 8 layers of Perlon, while the second was based on 8 layers of fiberglass. A tensile and a fatigue test had been used to investigate the mechanical properties of the AFOs' material. The findings revealed that the yield strength (Ϭy) is 42.897 MPa, the tensile strength (Ϭult) for Perlon is 42.993 MPa, and the elongation at break is 1.138 mm, whereas fiber glass has a tensile strength (Ϭult), yield strength (Ϭy), and elongation at break of 224 MPa, 170 MPa, and 2.17 mm, respectively. Additionally, the gait cycle and the collected data on distributed pressure are measured using force plates and F-socket devices. The patellar tendon-bearing model was constructed using the SolidWorks software tool. In addition, for the fiber glass and Perlon PTB orthosis models, the total deformation, safety factor of fatigue, and Von-Mises stress were calculated using the FEM (ANSYS). The safety factor of fatigue values for the material PTBO with 8 layers of fiber glass was 2.2895, and for 8 layers of Perlon, it was 0.083515. [ABSTRACT FROM AUTHOR]

Braided composites are gaining attention in the most industrial applications. To design rods with optimal tensile properties against combined loads, experimental studies were conducted to investigate the effect of using axial yarn and core in different categories on the tensile properties of braided reinforced composite rods. In this study, six types of braided composite rods with different arrangements of braid components (axial yarn or core type) were produced using glass and polyester fibers with epoxy resin as the matrix. The elastic modulus, ultimate tensile strength, and work of fracture of these rods were tested, and the experimental elastic modulus of samples were compared with previously developed models. Moreover, comparing the stress-strain results of the samples revealed that the produced hybrid samples demonstrate pseudo-ductile tensile behavior, showing varying trends as the type of reinforcement is altered. The results indicate that using a double-layer triaxial braid as reinforcement for the composite can increase the elastic modulus up to 13% compared to the similar single-layer sample. Additionally, employing a double-layer triaxial braid as reinforcement for the composite leads to a greater work of fracture. However, in terms of ultimate tensile strength, biaxial braid reinforcement demonstrates better performance in reinforcing the composite rods. [ABSTRACT FROM AUTHOR]

In the present study, the influence of nickel (Ni) and silicon (Si) additions to the Ti-15 V-3Al-3Cr-3Sn (Ti-15-3) fillers on microstructure and mechanical properties of Ti-15-3 gas tungsten arc (GTA) weldments was investigated. Controlled amounts of Ni and Si as grain refiners were introduced into the molten pool of Ti-15-3 alloy by pre-placing the cast inserts (Ti-15-3-x wt.% Ni (x = 0.15, 0.30, 0.5) and Ti-15-3-xwt.% Si (x = 0.15, 0.30, 0.50)) by GTA welding (GTAW). Microstructural examination of welds with Ni and Si additions revealed refined grains in the fusion zone (FZ) characterized by nonlinear grain boundaries. The grain refinement that is mainly caused by Ni and Si additions develops constitutional supercooling (CS) ahead of the solid–liquid (S/L) interface in the FZ. It has been shown that welds prepared with Ti-15-3-0.5 Ni filler (yield strength (YS) of 688 ± 6 MPa, ultimate tensile strength (UTS) of 721 ± 5 MPa, and % elongation (%El) of 9 ± 0.5%) and Ti-15-3-0.5 Si filler (YS = 693 ± 6 MPa, UTS = 725 ± 5 MPa, %El = 8 ± 0.5%) exhibited higher strength compared to autogenous weld (YS = 575 ± 4 MPa, UTS = 597 ± 4 MPa, %El = 11 ± 0.5%). The increased strength observed in welds made using Ti-15-3-0.5Ni filler and Ti-15-3-0.5Si filler can be attributed to the narrower width of columnar β grains and the presence of equiaxed grains in the FZ. Post-weld heat treatment (PWHT) for all the weldments resulted in improved tensile strength and hardness of the weldments, which was attributed to the fine and uniform precipitation of the α phase in FZ. [ABSTRACT FROM AUTHOR]

This paper presents the results of research on the technical–economic optimization of FDM parameters (Lh—layer height and Id—infill density percentage) for the manufacture of tensile and compression samples from recycled materials (r) of PETG (polyethylene terephthalate glycol) and ASA (acrylonitrile styrene acrylate) in the context of the transition to a circular economy. To carry out our technical–economic study, the fundamental principle of value analysis was used, which consists of maximizing the ratio between Vi and Cp, where Vi represents the mechanical characteristic (tensile strength or compressive strength) and Cp represents the production cost. The results of this study showed that, in the case of tensile samples manufactured by recycled PETG (rPETG), the parameter that significantly influences the results of the Vi/Cp ratios is Lh (the height of the layer), while for the samples manufactured additively from recycled ASA (rASA), the parameter that decisively influences the tensile strength is Id (the infill density percentage). In the case of compression samples manufactured by FDM from recycled PETG (rPETG) and recycled ASA (rASA), the parameter that signified influences the results of the Vi/Cp ratios is Id (the infill density percentage). Following the optimization of the FDM parameters, using multiple-response optimization, we identified the optimal parameters for the manufacture of parts by FDM from rPETG and rASA: Lh = 0.20 mm and Id = 100%. The results of this study demonstrated that the use of recycled plastics from PETG and ASA lends itself to a production and consumption model based on a circular economy. [ABSTRACT FROM AUTHOR]

Cast aluminum alloys have been increasingly used in internal combustion engine cylinder head applications because of their lightweight and high thermal conductivity. Increasing demand for fuel economy and high power density has posed a significant challenge on existing cast aluminum alloys for high temperature performance. This paper reports a study of evaluating two new high temperature cast aluminum alloys Al–Q (AlSiCuMg) and ACMZ (AlCuMnZr) using semi-permanent mold (SPM) cast cylinder heads. While the new cast aluminum alloys, especially the ACMZ alloy, show a significant improvement in high temperature tensile properties, they exhibit similar fatigue performance as the commonly used cylinder head aluminum alloy A356+0.5%Cu. This is due to the presence of casting defects which is limited by existing casting processes for cylinder heads. [ABSTRACT FROM AUTHOR]

Background/aim Debris accumulation beneath the dentures initiates countless difficulties such as inflamed oral mucosa and denture stomatitis. Denture stomatitis is a prevalent pathologic illness that is commonly linked to Candida albicans. Accordingly, treatment requires applying effective anti-inflammatory and antifungal medicaments that do not negatively influence the properties of denture base materials. Antifungal oral gel and ozonated water have quite an impact on inhibiting Candida albicans growth and treating denture stomatitis, so they have been selected in this research. This study aimed to compare the effect of antifungal oral gel and ozonated water on the tensile and compressive strengths of poly methyl metha acrylate (PMMA) and Nylon or polyamide denture base materials. Patients and methods This study was carried out for two types of denture base materials; group I PMMA and group II Nylon or polyamide. Total samples for both groups were 160 and fabricated following American Dental Association specifications No.12 for assessing tensile and compressive strengths. For each group (80 samples each group), the compressive strength was measured before (10 samples each) and after (10 samples each) the application of antifungal oral gel (10 samples each), and ozonated water (10 samples each), overnight for 15 days for each. Also, the tensile strength was measured for each group before (10 samples each) and after (10 samples each) the application of antifungal oral gel (10 samples each) and ozonated water (10 samples each) overnight for 15 days for each. Comparison between pre and post measurements was accomplished by Paired t-test, while comparison between heat-cure PMMA and nylon was carried out by using an Independent t-test. Results PMMA was significantly affected by ozonated water regarding compressive (P =0.0001) and tensile (P =0.0001) strength while antifungal oral gel had a significant effect only on the tensile strength (P =0.0001) but not the compressive strength (P =0.57). Both antifungal oral gel (P =0.7) and ozonated water (P =0.75) have insignificant effects on the compressive strength of nylon denture base material and also insignificant effect on tensile strength of nylon denture base material (P =0.16) for ozonated water and (P =0.37) for antifungal oral gel. Conclusion Ozonated water could adversely impact both the compressive and tensile strength of PMMA denture base material and the antifungal oral gel could affect only its tensile strength. Ozonated water and antifungal oral did not affect the compressive and tensile strength of the nylon denture base material.

Additive manufacturing (AM) is revolutionizing various industries by enabling the creation of complex structures with minimal waste. In the context of a circular economy, the importance of recycling cannot be overstated, as it plays a crucial role in reducing environmental impact and conserving resources. This study investigates the mechanical behavior of PETG in the context of recycling for 3D printing applications. With plastic waste posing significant environmental challenges, the pursuit of sustainable solutions is paramount. PETG has emerged as a promising material in additive manufacturing due to its favorable properties, but its sustainability remains a concern. Through mechanical testing, including tensile, compression, and impact tests, PETG specimens are evaluated after one cycle of recycling and reutilization

Highlights Nanocomposites of functionalized graphene (FG) and polyamide 6 (PA6) were prepared through the twin‐screw extrusion method by the routes of solution‐assisted masterbatch technique and dry mixing of nanomaterials with the virgin polymer. Scanning electron microscopy (SEM), X‐ray diffractometry (XRD), Raman spectroscopy, Rheological analysis, and tensile tests were performed to determine the best nanocomposite manufacturing route. The dispersion state proved to be the best for the 1 wt% FG/PA6 nanocomposite (1‐FG) prepared by the dry mixing method based on the characterization and analysis methods performed. Tensile properties were noticeably improved for the 1‐FG nanocomposite by 32.7% and 8.7% for Young's modulus and tensile strength, respectively. The presence of a network of nanomaterials was also spotted in SEM and rheological analysis. It was also found that the presence of trapped solvent molecules for the masterbatch solution method resulted in altered tensile properties and lowered rheological enhancements compared with its dry‐mixed counterparts. Raman spectroscopy was also proven capable of analyzing the degree of dispersion analogous to XRD or rheological analysis for the first time. Furthermore, the presence of vacuum degassing during the melt processing of nanocomposites was experimentally proven to be a must since FG particles get in‐situ reduced by the high temperature of the melt processing, resulting in the generation of gaseous species that critically sabotage melt processing in the absence of vacuum. Reduction of graphene in the melt processing sabotages the process. Vacuum degassing controls gaseous species generated due to graphene reduction. Dry mixing of materials proved to be better than the solution masterbatch method. Raman is capable of analyzing dispersion quality analogous to rheometric mechanical spectrometer (RMS) and XRD. In the solution masterbatch path, graphene retards solvent removal in degassing. [ABSTRACT FROM AUTHOR]

The study focus on fiber‐reinforced polymer composite materials, which are widely used in the mechanical industries for various applications. While using the composite materials, mechanical properties such as tensile, flexural, and interlaminar shear strength plays vital role in selection of composite materials. The current work aims to investigate the influence of adding nanosilica at varying weight percentages (0, 2, and 4) to the epoxy matrix on the tensile, flexural, and interlaminar shear strengths of the fiber‐reinforced polymer hybrid nanocomposite. The five carbon and four Kevlar layer hybrid polymer nanocomposites are made with woven fibers. The method used to improve the dispersion of nanosilica in the epoxy resin was high‐speed shearing. The hand lay‐up process was used to manufacture hybrid polymer nanocomposite laminates, which were then effectively postcured. The tests for tensile strength, flexural strength, and interlaminar shear strength were carried out in accordance with ASTM standards D3039, D790, and D2344, respectively. According to the tested specimens, a hybrid composite including 2 wt.% of nanosilica with epoxy provides better tensile strength of 6.83%, flexural strength of 10.13%, and interlaminar shear strength of 13.54% more than a hybrid composite without nanosilica. At 4 wt.% of nanosilica addition to epoxy matrix, the tensile, flexural, and interlaminar shear strength decreased when compared to 2 wt.% of nanosilica due to agglomeration. The addition of 2 wt.% nanosilica to the epoxy matrix in carbon/Kevlar fiber‐reinforced polymer hybrid composites yields superior tensile, flexural, and interlaminar shear strength compared to other weight percentages. [ABSTRACT FROM AUTHOR]

In the present investigation, the effect and role of plasma gas flow rate on the formation of microstructure, weld defects and plasma modes during plasma arc welding of Ti6Al4V titanium alloy were studied using microscopic examinations, energy dispersive spectroscopic analysis, tensile tests and microhardness measurements. Plasma gas flow rate influences the arc pressure, arc constriction and stability. The transformation of plasma arc from conduction mode to keyhole mode causes severe changes to the microstructural characteristics of the titanium welds. This transformation takes place with small variations of PGFR. The formation of excess weld metal out of weld bead observed at the bottom of the weld is attributed by the formation of keyhole. The macrostructural examination shows that the weld geometries increases and weld defects such as lack of penetration and porosity decreases with increase in the PGFR. The microstructural examination shows that there are various phases formed during variation in PGFR. Acicular α and Widmanstätten α were observed considerably in all the welded joints. Strength of the welded joints and hardness increases with increase in plasma gas flow rate. In the joint welded with 1 L/min, there is formation of α-case which is an oxygen rich brittle subsurface structure and found detrimental to the ductility of the joints. [ABSTRACT FROM AUTHOR]

This study investigates the quasi-static and viscoelastic properties of additively manufactured (AM) PETG reinforced with short carbon fibres. Samples were manufactured using different parameters in terms of the infill pattern, porosity, and annealing condition. Tensile and compressive tests were conducted to determine quasi-static properties such as Young's modulus and toughness, and dynamic mechanical analysis was used under a frequency sweep of 1–100 Hz to describe the viscoelastic behaviour of the composites. The major impacts and responses between the print parameters were quantified using Analyses of Variance (ANOVAs), which revealed the major contributor to each mechanical property. Fractography on the tensile samples using scanning electron microscopy demonstrated fibre pull-out, indicating poor fibre–matrix bonding, but also revealed interfacial bonding between raster lines in the annealed samples. This had a prominent effect on the properties of latitudinal samples where the force applied was perpendicular to the raster lines. Generally, porosity appeared to have the greatest contribution to the variance in the mechanical properties, with the exception of the tensile modulus, where the infill pattern had a more substantial effect. Annealing caused a consistent increase in the tensile modulus of the tested samples, which can be used to support the design and optimisation of AM parts when they are used under specific loading conditions. [ABSTRACT FROM AUTHOR]

The 3 K and 6 K (meaning that 3000 or 6000 carbon filaments are contained in one bundle) carbon fibers were embedded by pure aluminum sheets to have a sandwich composite structure under the accumulative roll bonding method. The tensile and cupping tests were carried out to reveal the strengthening mechanism of carbon fibers embedded in the aluminum+carbon fibers composite sheets. The improvements of ultimate tensile and cupping strengths of aluminum+carbon fibers composite sheets reached to be as high as 48 % and 38 %, compared with that of as‐received sheets. With the detailed observation of the tensile and cupping fractures, the underlying strengthening mechanism comes from the bridging effect of carbon fibers during tensile and cupping tests. The accumulative roll bonding method was approved to be an effective way for aluminum+carbon fibers composite sheets preparation with higher tensile and cupping strength. [ABSTRACT FROM AUTHOR]

The current study deals with the influence of changing volume fractions and particle sizes on the fracture behavior of three different types of composite materials. Two various kinds of natural materials (cow and sheep bones) were employed to reinforce the polyester resin and manufacturing three types of composites made of cow, sheep, and hybrid (cow/sheep) bones reinforced polyester. Maximum fracture loads were measured experimentally using a standard destructive method of tensile and flexural testing. A variety of sieves (425 µm, 600 µm, 710 µm, 850 µm, 1180 µm, and 1700 µm) were utilized in order to examine its impact on the samples under both tests. The eight volume fractions which were adopted to fabricate the specimens were (20%, 25%, 30%, 35%, 40%, 45%, 50% and 55%). Many samples were examined for each test and type. For all three types of the specimens, the findings revealed that the lowest particle size causes an increase of the tensile and flexural loads. These results of loads decrease with increasing particle size. The results also detected that the smallest ratio of the volume fraction gives the highest fracture load for both tests. The comparison between the cow/polyester, sheep/polyester and hybrid (cow-sheep/polyester) composites showed that the tensile and flexural loads are organized in a descending order as follows: Sheep/polyester, hybrid/polyester, and cow/polyester. [ABSTRACT FROM AUTHOR]

This investigation is effort to enhance the mechanical properties on friction stir welded Al-Mg alloy with different processing levels like tool pin profiles, tool rotational speed and welding speed and the other parameters like tool tilt angle and tool axial load is kept constant for all the runs. The tool pin profiles (straight pentagonal cylinder (SPC), straight cylinder (SC) and straight fluted cylinder (SFC)), tool rotational speed (1000, 1300 and 1600 rpm) and tool traverse speed (30, 40 and 50 mm/min) is processing input factors. Those FSWed samples are considered to conduct the mechanical properties like tensile strength and microhardness is investigated. The optical microscope investigations are utilized to identify the finer grain structure on welded Al-Mg alloy. The ultimate tensile strength is attained at the processing levels (1000 and 1600 rpm, 30 and 50 mm/min and SPC and SC). The maximum hardness was attained on the stirred zones of FSWed Al-Mg alloy for the process parameters (1300 rpm, 30 and 40 mm, SFC and SC), respectively. The poorer grain structure was attained on the stirred regions of Al-Mg alloy due to mechanical mixing is not properly maintained by the selected processing parameters. The microstructure of friction stir welded Al-Mg alloy shows the better fine refinement due to enhancing stirring action by the optimal process parameters. [ABSTRACT FROM AUTHOR]

Composite materials are gaining popularity due to their better mechanical qualities and low weight. This study focuses on enhancing forces of flexural and tensile characteristics in epoxy-based composites by incorporating reinforced carbon fibers extracted from pineapple leaves in combination with cobalt filler. The reinforcement of natural fibers in composite materials addresses environmental concerns and contributes to improved mechanical attributes. Hand lay-ups of pineapple leaf fiber (PALF) and epoxy compound by carbon fiber were created proportion of weight (wt%) by adjusting cobalt 0.25 to 1.0 wt%. The flexural strength of PALF is around 101 MPa, and the Tensile strength of PALF is around 92.94 MPa. Whereas the Flexural strength of CF is around 343.54 MPa, and the Tensile strength of CF is around 181.32 MPa. Compared to pure epoxy, 51.25% increased strength and considerable improvement of flexural and tensile specimens. 0.5 wt% inclusion of nano Cobalt filler component confirms favorable strength test findings in PALF/CF epoxy combination. [ABSTRACT FROM AUTHOR]

This study explores the mechanical properties of a novel composite material, blending polylactic acid (PLA) with sea shells, through a comprehensive tensile test analysis. The tensile test results offer valuable insights into the material's behavior under axial loading, shedding light on its strength, stiffness, and deformation characteristics. The results suggest that the incorporation of sea shells decrease the tensile strength of 14.55% and increase the modulus of 27.44% for 15 wt% SSP (sea shell powder) into PLA, emphasizing the reinforcing potential of the mineral-rich sea shell particles. However, a potential trade-off between decreased strength and reduced ductility is noted, highlighting the need for a delicate balance in material composition. The study underscores the importance of uniform sea shell particle distribution within the PLA matrix for consistent mechanical performance. These results offer a basis for additional PLA-sea shell blend optimization, directing future efforts to balance strength, flexibility, and other critical attributes for a range of applications, including biomedical devices and sustainable packaging. This investigation opens the door to more sustainable and mechanically strong materials in the field of additive manufacturing by demonstrating the positive synergy between nature-inspired materials and cutting-edge testing techniques. [ABSTRACT FROM AUTHOR]

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The conventional techniques for producing a socket are time-consuming disproportionate to the significant population afflicted by limb amputations. Although the new manufacturing direct method, the modular socket system (MSS) method, involves reduced labor time, the technique produces sockets with high stiffness that cause discomfort for those with lower limb amputations during walking. This study investigated the tensile characteristics of numerous materials in below-knee prosthetic sockets. Initially, a vacuum molding approach was used to produce the sockets, which involved various polymers and composite materials to improve the prosthesis socket properties. An F-socket device was also employed to ensure efficient production and optimized pressure distribution at the interface between the socket and the residual limb. A SOLIDWORKS® software was then applied to determine the numerical analysis (stress distribution and the maximum internal pressure). The samples from Group E involved utilizing a novel mixture compared to the direct and traditional methods of various materials. This study presents a novel prosthetic limb socket made from a mixture of four carbon fiber layers, utilizing 20% polyurethane resin and 80% acrylic as the matrix. The resulting material demonstrated acceptable stiffness, extended socket life, and reduced curing time. During the patient's gait cycle, peak pressure of 300 KPa was recorded using the F-socket, while SOLIDWORKS® software indicated an internal pressure of 343 KPa, aligning closely with F-socket measurements. The new direct-fit socket design prioritizes comfort and flexibility using materials with reduced stiffness. [ABSTRACT FROM AUTHOR]

Hybrid composites are made by fusing together, typically using resin, a matrix material (typically metal), a fiber, and a filler component. Fibers and particles are encased in a matrix of another material to create modern composites. Natural fiber composites are becoming increasingly popular due to rising awareness of their many practical applications. The debris produced by the seashell farming becomes serious environmental threat. Recent research has centered on the potential applications of this seashell waste. The purpose is to reduce seashell waste that pollutes the coast near Kanyakumari. Agricultural waste, such rice husk, is more accessible than other types of biomass. Conventional materials are weighed more, so lightweight materials can be used as alternatives for the structural components of an automobile. This swatch is made from combination of biocomposite and repurposed seashells. Mechanical tests, including tensile, flexural, impact, and hardness testing, were performed on the prepared samples. The morphological analysis shows good laminar and interfacial connections throughout the structure. The EDAX spectrum shows the presence of elements like silicon, sulfur, and zinc. The EDAX spectrum of C5 hybrid biocomposites (40% rice husk + 10% seashell + 50% polyester resin) has more zinc than silicon. The C2 (10% rice husk + 40% seashell + 50% polyester resin) hybrid composite outperforms other composites in tensile strength (51.47 MPa), Brinell hardness (132BHN), Rockwell hardness (62RHN), impact energy (51.4 J), flexural strength (203.03Mpa), and water absorption (1%). Based on research investigations, hybrid biocomposites made of bio seashell and bio rice husk are superior than standard biocomposites without sacrificing the eco-friendliness of the automobile. [ABSTRACT FROM AUTHOR]

In transportation engineering, road pavement is commonly categorized as either flexible pavement or rigid pavement. The pavement demonstrates a distinct capacity to endure a variety of loads, including compressive and tensile loads. The capacity to endure compressive and tensile forces is extremely important, especially in the field of pavement construction, as it ensures both the longevity and the safety of the pavement. The objective of this study was to evaluate the capacity of hot mix asphalt to endure compressive and tensile pressures. The experimental methodology employed four different wire mesh deployment configurations on hot asphalt mixtures, utilizing three-point flexural test equipment. The data indicates the most effective method for mimicking hot mix asphalt involves adding a wire mesh layer at a depth of 30 mm below the surface of the experimental specimen. The particular modeling method showed a measurement of flexural resistance up to 291.85 kN. The study's findings indicate that the hot asphalt mixture exhibits a state of balance in its capacity to endure both compressive and tensile pressures. Incorporating a wire mesh layer within the middle section of the hot asphalt mixture has been perceived to enhance its ability to withstand tensile loads, hence improving its overall performance. [ABSTRACT FROM AUTHOR]

The utilization of 20CrNiMo/Incoloy 825 composite materials as high-pressure pipe manifold steel can not only improve the strength and hardness of the steel, but also improve its corrosion resistance. However, research on the heat treatment of 20CrNiMo/Incoloy 825 composite materials is still scarce. Thus, the aim of this study was to investigate the influence of solid solution treatment on the microstructure and properties of 20CrNiMo/Incoloy 825 composite materials. Firstly, the composite materials were subjected to solid solution treatment at temperatures ranging from 850 to 1100 °C with varied holding times of 1 h, 4 h, and 6 h. Microstructural analysis revealed that the solid solution treatment temperature had a more pronounced effect than the treatment time on the interface decarburization layer, carburization layer, and grain size. It was observed that the carburized layer thickness decreased while the decarburized layer thickness increased with an increase in the solid solution treatment temperature, oil cooling was found to enhance the hardness of the base layer of the composite materials, and the size of the original austenite grains of 20CrNiMo steel and Incoloy 825 increased with an increase in the solid solution treatment temperature. Secondly, the tensile properties, microhardness, and fracture morphology were evaluated after the composite materials underwent solid solution treatment at temperatures between 950 °C and 1100 °C for 1 h. The results indicated that increasing the solution temperature initially led to an increase in tensile strength and elongation after fracture, followed by a decrease; furthermore, the hardness of Incoloy 825 exhibited a declining trend, while the hardness of 20CrNiMo first decreased then increased. Thirdly, the shear properties and interfacial element diffusion of the composite materials were analyzed following solid solution treatment in a temperature range of 950 °C to 1100 °C for 1 h. The findings demonstrated that higher solid solution treatment temperatures induced full diffusion of Cr, Ni, and Fe atoms at the interface and softened the matrix, leading to an increase in the thickness of the diffusion layer and toughening of the composite interface. Therefore, the shear strength increased with an increase in the solid solution treatment temperature. Finally, the optimal solid solution treatment process for 20CrNiMo/Incoloy 825 composite materials was determined to be 1050 °C/1 h oil cooling, following which the composite materials had good comprehensive mechanical properties. [ABSTRACT FROM AUTHOR]

The present study referred to the lightweight cenosphere filled, and epoxy composites (0, 7.5, 15, and 22.5 vol.%.) developed with the help of the hot compression moulding process. To ensure the strength of composites, the prepared system was analyzed with tensile, flexural, impact properties, and dynamic mechanical characteristics discussed. Cenosphere-filled composites attained the maximum tensile strength of 19.5 MPa, which is 60% better than the neat epoxy. Adding cenosphere particles increases the tensile, flexural, and impact strength at a superior level. Dynamic mechanical analysis revealed that in 22.5 vol.% of cenosphere reinforced composites, energy dissipation and maximum storage modulus of 6 MPa was enhanced. The surface morphologies of the fractured specimens were characterized using scanning electron microscope (SEM). The morphological investigations indicate a good state of particle distribution in the epoxy matrix. [ABSTRACT FROM AUTHOR]

Nickel foam offers excellent conductivity, a high surface area, and lightweight structure, making it ideal for applications, like battery electrodes, catalysts, and filtration systems. Its durability and corrosion resistance further enhance its performance in various industries. However, few studies focus on the tensile anisotropy of nickel foam and its tensile fracture process. In this study, the anisotropic tensile behavior of nickel foam with varying relative densities has been investigated, along with its tensile fracture behavior using in situ techniques. The tensile properties of nickel foams show strong anisotropy due to the flattening process in the production process. The results show that the tensile properties, including the yield strength, tensile strength, and elastic modulus, increase with the increasing relative density, while the elongation percentage has no relationship with the relative density. The experiment data on tensile strength are in agreement with Gibson's formula and Liu's formula. In situ tensile tests are conducted to explore the microscopic fracture mechanism of nickel foam. The results show that the struts of nickel foam are tensile fractures or shear fractures near the joints, and the fracture process of struts is clearly recorded and analyzed. This study is significant as it provides critical insights into the anisotropic tensile behavior of nickel foam and fracture mechanism, enabling the optimization of production processes and broadening its potential applications. [ABSTRACT FROM AUTHOR]

The growing need for sustainable materials in engineering applications has led to increased interest in the use of waste-derived ceramics as reinforcing fillers in polymer composites. This study investigates the mechanical and tribological performance of epoxy composites reinforced with Yttria-Stabilized Zirconia (YSZ) waste ceramics, focusing on the effects of varying ceramic content (0–40 wt.%). The results demonstrate that while the tensile strength decreases with increasing ceramic content, the wear resistance and surface hardness improve, particularly at 20 wt.% YSZ. These findings are highly relevant for industries such as automotive, aerospace, and industrial manufacturing, where the demand for eco-friendly, high-performance materials is growing. This work aligns with the journal's focus on sustainable engineering by offering new insights into the practical application of waste materials in high-performance composite systems. [ABSTRACT FROM AUTHOR]

Polymer optical fibers (POFs), including side‐emitting POF (SEPOF) and end‐emitting POF (EEPOF) are developed for luminous textiles. The SEPOF is more common for usage but suffers from significant intensity decay, which limits its effective usage length. In contrast, the EEPOF can provide a much more stable side illumination behavior than SEPOF since the light is largely confined within the EEPOF, while its side illumination requires special treatment. In this work, 0.5 mm diameter EEPOFs were firstly assembled into bundles with 10 EEPOFs (B10) and 15 EEPOFs (B15), and then twisted. The morphology, tensile properties, and side illumination behavior of the twisted EEPOF bundles are evaluated. With an increased twisting degree, the initial modulus of twisted sample B10 increases (due to shortening of bundle diameter) from 1.06 to 1.17 GPa while the initial modulus of twisted sample B15 decreases from 1.01 to 0.91 GPa. The increased twisting degree also results in the higher flexibility (indirectly connected with modulus) of the twisted EEPOF bundles. Besides, the increased twisting degree results in a higher side illumination intensity meantime causes a decreased side illumination intensity along the light penetration path. When the twisting degree is low (e.g., 10 T m−1), the highest decrease rate of side illumination intensity along the light penetration path is found. [ABSTRACT FROM AUTHOR]

The combined actions of tensile and ultrasound on the melting enthalpy, retrogradation kinetics, spherical morphology, crystal structure, thermal stability, hydrophilicity, and molecular chain of thermoplastic cassava starch (TPS) containing different surface properties nano‐silica (SiO2) are investigated. The result indicates that the melting enthalpy of TPS/SiO2 composite and the retrogradation rate increases under combined actions of tensile and ultrasound, and the sample containing hydrophobic nano‐SiO2 is greater than that of hydrophilic nano‐SiO2. The spherulites of TPS/SiO2 composite become obvious, and the contact angle increases; however, the thermal degradation temperature decreases. Under combined actions of tensile and ultrasound, the aggregation of nano‐SiO2 particles in the matrix reduces and the dispersion become uniform. TPS/SiO2 composite presents A+V type crystal structure, and V‐type crystal increases after the combined actions of tensile and ultrasound. The storage modulus, loss modulus, and glass transition temperature of TPS/SiO2 composite increase, and the sample containing hydrophobic nano‐SiO2 is higher than that of sample containing hydrophilic nano‐SiO2. [ABSTRACT FROM AUTHOR]

This paper reports improvement in the tensile, flexural and interlaminar shear strength (ILSS) properties of ADG‐NH2/Epoxy/CFRP composites at low filler content. Five symmetrical CFRP composite laminates were prepared through wet layup process assisted by vacuum bagging technique with varying wt% proportions (0.25, 0.5, 0.75 and 1) of ADG‐NH2/Epoxy. Tensile tests, short beam shear test and flexural tests were carried out as per ASTM D3039, ASTM D2344 and ASTM 790‐10 respectively to assess the effect of the ADG‐NH2 functionalized nano additives on their mechanical properties. The variation in ILSS were studied for varying temperatures (room temperature, 35, 50, 75, 85, & 100°C for each type of ADG‐NH2/Epoxy wt% (neat, 0.25, 0.5, 0.75 & 1)) of ADG‐NH2/Epoxy/CFRP composites. The ILSS was enhanced up to ∼27% for 0.5 wt% of ADG‐NH2 reinforced CFRP at room temperature but reduced with the higher concentrations (0.75 wt% & 1 wt%). It was observed that ILSS reduced with gradual temperature variations up to 100°C w.r.t room temperature. But an increment was observed up to 0.5 wt% for ADG‐NH2 for all temperature. Form the test results, it has been recorded an improvement in mechanical properties that is, the elastic modulus by ∼18%, ultimate tensile strength by ∼21%, % elongation at break by∼19% and toughness by∼28% for the 0.5 wt% of ADG‐NH2 graphene nano additive reinforced CFRP composite laminates as compared to neat epoxy CFRP laminates. Results also show the augmentation in the Max load by ∼24%, flexural strength by ∼33%, flexural modulus by ∼43%, and flexural strain by ∼26% were observed for the 0.5 wt% of ADG‐NH2 graphene nano additive reinforced CFRP composite laminates as compared to neat epoxy CFRP composite laminates. Fractographic studies of fractured surface using SEM analyses shows better adhesion mechanisms which supports the augmentation in mechanical properties with addition of amine functionalized graphene to CFRP laminate. Highlights: Reinforcement of amine functionalized (ADG‐NH2) graphene in the epoxy matrix and incorporation with carbon fibers to enhance the interfacial and flexural properties.Evaluation of temperature effects on interlaminar shear strength properties of amine functionalized CFRP compositesImprovements in tensile, ILSS and flexural properties observed for a low percentage (0.5 wt%) of ADG‐NH2 graphene reinforced CFRP composite laminates.Use of aerospace grade epoxy and resin with amine functionalized graphene for further use in aerospace industry applications. [ABSTRACT FROM AUTHOR]