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A model based on the fitting of stress–strain data by tensile tests of bio-composites made of a bioplastic (polybutylene succinate (PBS)) and brewer spent grain filler (BSGF) is developed. Experimental tests were performed for various concentrations of BSGF in the range from 2% to 30%. The model is suitable for describing the elastic–plastic behavior of these materials in terms of two mechanical parameters, tensile stress and tensile stiffness (or Young's modulus), depending on the filler concentration. The mechanical characteristics, derived from the fit parameters, show good agreement with the experimental data. The mathematical model used here could be an important aid for the experimentation and manufacturing process as it allows the prediction of the mechanical tensile parameters of a mixture with different filler concentrations, avoiding the long and complex preparation cycle of bio-composites, as well as the specific mechanical tests. The physical properties required by the objects created with the PBS–BSGF bio-composite by the partners/stakeholders of the research project co-financing this research can be quite different; therefore, a mathematical model that predicts some of the mechanical properties in terms of the mixture composition may be useful to speed up the selection of the required amount of BSGF in the mixture. [ABSTRACT FROM AUTHOR]

This paper deals with Barkhausen noise in Trip steel RAK 40/70+Z1000MBO subjected to uniaxial plastic straining under variable strain rates. Barkhausen noise is investigated especially with respect to microstructure alterations expressed in terms of phase composition and dislocation density. The effects of sample heating and the corresponding Taylor–Quinney coefficient are considered as well. Barkhausen noise of the tensile test is measured in situ as well as after unloading of the samples. In this way, the contribution of external and residual stresses on Barkhausen noise can be distinguished in the direction of tensile loading, as well as in the transversal direction. It was found that the in situ-measured Barkhausen noise grows in both directions as a result of tensile stresses and the realignment of domain walls. The post situ-measured Barkhausen noise drops down in the direction of tensile load due to the high opposition of dislocation density at the expense of the growing transversal direction due to the prevailing effect of the realignment of domain walls. The temperature of the sample remarkably grows along with the increasing strain rate which corresponds with the increasing Taylor–Quinney coefficient. However, this effect plays only a minor role, and the density of the lattice imperfection expressed especially in terms of dislocation density prevails. [ABSTRACT FROM AUTHOR]

Geosynthetics are widely used in reinforced soil engineering because of their excellent performance. Currently, an increasing number of researchers are studying the fabrication of geosynthetics with both reinforcement functions and sensing abilities. Sensor-enabled piezoelectric geobelts (SPGBs) have great potential in the field of integrated soil reinforcement monitoring because of their ability to reinforce and sense soil. In this paper, polymer-based SPGBs that can be batch extruded were successfully prepared using high-density polyethylene (HDPE), polyolefin elastomer (POE), carbon black (CB), and piezoelectric ceramics (PZT), and the preparation rate of SPGBs was substantially improved. Laboratory tensile tests were conducted to test the strain–stress–impedance–voltage signals of SPGB in the tensile process at 45 different ratios. The results showed that the piezoelectric strain constant (d33) of SPGBs was up to 10.5 pC/N. The tensile strength and breaking strain of SPGBs reached their maximum values of 14 MPa and 26.37%, respectively, at 65% PZT content. During the tensile test, the SPGB normalized impedance increased with increasing strain, and there was a significant sudden increase at the time of damage. An empirical formula for strain-normalized impedance, which can be used to calculate the strain of SPGBs quantitatively, was established. The SPGB output voltage rapidly increased and then decreased with increasing strain, and two characteristic points can be used as warning signs to qualitatively describe the change of SPGBs. The results of this study can provide a design basis for the batch preparation of SPGBs in engineering. [ABSTRACT FROM AUTHOR]

The plasma electrolytic oxidation (PEO) technology was used to prepare ceramic coating on the surface of titanium alloy to prevent the galvanic corrosion of AH36/TC4(PEO). The results showed that after PEO treatment, ceramic coating with micropores was formed on the substrate surface. When the voltage was low, the pore size was small. With the increase of voltage, the thickness and the pore sizes of the coating increased. After PEO process, the average galvanic corrosion rate was reduced by 60%, and the number of pitting pits on the AH36 surface in the galvanic pair was reduced. The tensile strength and elongation of AH36 coupled with TC4(PEO) decreased by 4.0% and 11.9%, respectively. The contents of the corrosion products Fe2O3·H2O and FeO(OH) decreased, and the corrosion area of the tensile specimen was evidently reduced. Therefore, the PEO process can effectively reduce the galvanic corrosion susceptibility of AH36/TC4(PEO), alleviate the reduction degree of ductility and toughness of anode AH36, and enhance the corrosion resistance performance. [ABSTRACT FROM AUTHOR]

This work proposes that a non-bleeding modified asphalt-based grouting material (AG) can be used to improve the durability performance of prestressed tendon (PT) in post-tensioned concrete structures (PTCS). Therefore, durable and mechanical properties of PTs are tested and compared to PTs coated by AG, AH70 matrix asphalt (AH), epoxy resin (ER), respectively. The combined effect of different coatings on diffusion coefficient, strength and ductility are highlighted. Results showed that AG recorded higher enhancing impermeability than ER and exceeded by 1–2 orders of magnitude compared with traditional CG. Compared with the PS and AH, ER and AG can slightly improved the strength of the strands and significantly enhance the ductility by 50% or more. A corrosion constitutive model for different coated strands is proposed, which features excellent applicability and accuracy. Finally, based on the linear weighted sum optimization method, the protective effect of AG has been discussed and validated. Satisfactory responses have been found AG is effective in enhancing the durability of prestressed strands. [ABSTRACT FROM AUTHOR]

This work uses finite elements to build and examine composite laminates constructed of carbon fiber reinforced polymer (CFRP). The great strength compared to weight of composite materials is an important characteristic. Using the finite element method and the ANSYS program, the optimal resistance model for tensile testing and compressive testing was chosen. This article will present hybrid 3D simulation models of woven materials reinforced with fibers, with the goal of optimizing the model by adjustment of the reinforcement angle. The Math-Cad and ANSYS software will be used to compare these reinforced models from different angles in addition to testing them under compressive and tensile loads. The results of the tensile testing of the models were illustrated using von Mises stress theory of failure. Of all the models, the tenth is the one that is least susceptible to failure. The resistance to breakdown is weaker (51.5%) when compared to the resistance to the fifth model's breakdown. The von Mises stress theory of failure was used to illustrate the findings of the compressive testing of the models. The third model is the one that has the lowest failure probability. The resistance to collapse is significantly lower (48%) than the resistance to the fifth model's disintegration. Additionally, the results show that the sixth model had the lowest shear stress (1.5686 MPa), whereas the tenth model had the highest shear stress (22.734 MPa). For resistance to stresses, strains, and deformations caused by the tensile test and compression test, the third model is the best selection. [ABSTRACT FROM AUTHOR]

Recently, plaster has gained increasing attention as a mechanical and environmentally friendly option and is an effective alternative to traditional cement products. Additionally, polyester has an effective impact on the mechanical properties of materials, in addition to being one of the most environmentally friendly materials. However, studies are still ongoing to reach the best ratios of polyester resin, polyester hardener, and gypsum plaster that can improve mechanical properties. This research aims to investigate the impact of these components at various ratios (30%, 45%, and 60%) of gypsum plaster weight on the mechanical properties of plaster material. This study is carried out by conducting compression and tensile tests for three ratios, which are considered among the most important mechanical tests according to their applications. In addition, the environmental emissions resulting from the three different ratios of plaster are evaluated to determine their environmental impact. This study found that the largest ratio (30%) was the most effective from an economic and mechanical point of view, while achieving lower carbon emissions compared to the other ratios, which enhances the trend towards achieving the environmental goals of the Kingdom of Saudi Arabia's Vision 2030 to reach zero emissions. This study is highly significant both in terms of scientific research and practical application across a range of industries, since it integrates the enhancement of material performance with the achievement of environmental sustainability requirements. [ABSTRACT FROM AUTHOR]

This study looks at how welding intensity, speed, voltage, and stick-out affect the structural and mechanical characteristics of metal inert gas (MIG) welding on SUS 201 stainless steel and C20 steel. The Taguchi method is used to optimize the study's experiment findings. The results show that the welding current has a more significant effect on the tensile test than the welding voltage, stick-out, and welding speed. Welding voltage has the lowest influence. In addition to the base metals' ferrite, pearlite, and austenite phases, the weld bead area contains martensite and bainite microstructures. The optimal parameters for the ultimate tensile strength (UTS), yield strength, and elongation values are a 110 amp welding current, 15 V of voltage, a 500 mm.min−1 welding speed, and a 10 mm stick-out. The confirmed UTS, yield strength, and elongation values are 452.78 MPa, 374.65 MPa, and 38.55%, respectively, comparable with the expected value derived using the Taguchi method. In the flexural test, the welding current is the most critical element affecting flexural strength. A welding current of 110 amp, an arc voltage of 15 V, a welding speed of 500 mm.min−1, and a stick-out of 12 mm are the ideal values for flexural strength. The flexural strength, confirmed at 1756.78 MPa, is more than that of the other samples. The study's conclusions can offer more details regarding the dissimilar welding industry. [ABSTRACT FROM AUTHOR]

Natural fiber-based composites become more popular as the demand for lightweight, high-strength materials for specialized applications grows. Moreover, natural fiber-based composites have greater durability, stiffness, and damping resistance. Researchers developed a wide variety of composites for different applications. This study aims to develop a hybrid composite using Acacia arabica and Sida cordifolia fibers as a reinforcement and epoxy as a resin. The fibers were treated using 5% NaOH solution. Six samples were prepared by varying the proportion of fibers and resin. The performance of the composites was measured by conducting the tensile, flexural, impact, and hardness tests. The alkaline-treated sample with 70% fiber and 30% resin (S6) exhibits a greater tensile strength of 384 MPa which shows much improvement in tensile strength when compared to other samples. The mechanical properties of the hybrid composites are better than many other composites available in literature. The surface morphological analysis and water absorption tests were also carried out. [ABSTRACT FROM AUTHOR]

To develop a material with strong impact resistance, bending direction and in‐plane direction, the tensile and bending properties of sandwich films obtained by placing and re‐pressing a compression‐molded polypropylene sheet between two sheets of carbon‐fiber‐reinforced thermoplastics (CFRTPs) were evaluated. Three types of CFRTP were investigated, and thermoplastic nylon 66, polyurethane, and polyphenylene sulfite were used as the resin base materials to wrap the carbon fiber. Regarding the tensile properties of the sandwich films, the Young's modulus and maximum stress values were lower compared with those of the CFRTP sheets, regardless of the resin base material. However, improvements in elongation properties of 97%, 109%, and 156%, respectively were found, transforming the film into a softer and stronger film. Regarding the bending properties of the sandwich films, the Young's modulus and maximum stress values were higher compared with those of the CFRTP sheet. To examine the influence of the number of layers, the five‐layer sheet, in which the sandwich film was placed in two CFRTP sheets, exhibited inferior elongation properties to the three‐layer sheet during the tensile test. However, the results of the bending test found a significant improvement in Young's modulus of approximately 2.5 times and final strength of approximately three times. We anticipate that this material could be applicable to components requiring specific mechanical properties in both bending and in‐plane directions in future applications. Highlights: CFRTP sandwich sheets were fabricated using a simple hot‐press method.The sandwich sheet showed improved mechanical properties in the in‐plane directions.Both the tensile modulus and the bending modulus have reached the GPa‐order.The sandwich film in question had particularly excellent bending properties.The sandwich film showed dependence on the number of layers.In‐plane elasticity of the films was evaluated using a falling ball test. [ABSTRACT FROM AUTHOR]

The tensile properties of polyacrylonitrile (PAN)-based and pitch-based single carbon fibers were assessed using Raman scattering. Parameters and ratios related to Raman scattering and stress measurement for the G- and D-bands were analyzed. These include the peak values of Raman shifts (RG, RD), full width at half maximum (FWHMG, FWHMD), peak value slopes (|AG|, |AD|), peak value intercepts (BG, BD), the intensity ratio (ID/IG), the peak value ratio (RD/RG), the full width at half maximum ratio (FWHMD/FWHMG), the slope ratio (AD/AG), and the intercept ratio (BD/BG). These parameters and ratios were determined by analyzing the PAN-based and pitch-based carbon fibers and were correlated to the tensile modulus (E), interlayer spacing (d002), lattice spacing (d10), and crystalline size (Lc and La). In addition, a linear relationship was identified between the Raman scattering, stress measurement parameters, ratios and E, d002, d10, as well as between the Raman scattering, stress measurement parameters, ratios and La and LC on the log–log scale. [ABSTRACT FROM AUTHOR]

Digital Image Correlation (DIC) is a non-contact measurement method that identifies surface changes on a specimen by analyzing a sequence of photographs taken before, during, and after the loading process. DIC determines contour deformation, strain, and stress values by examining variations in the speckled pattern created by the random addition of black dots. In this research, DIC was used to visualize the graphical presentation of a uniaxial tensile test. To obtain stress and strain values, the study employed two methods: the conventional experimental uniaxial tensile test and the DIC method. Tensile steel specimens with five different thicknesses, ranging from 6 mm to 16 mm, were fabricated and tested. The specimens were cut at a 15-degree angle from the rolling direction from the same plate sheet for each thickness. It was discovered that the orientation of the applied forces can affect the changes in Young's modulus values, which are higher when the load is applied parallel to the direction rather than perpendicular to it. The open-source image correlation software package Ncorr, integrated with MATLAB, was used for DIC analysis. The results showed that both methods provided close values for tensile strength and Young's modulus. The DIC method produced slightly lower values than the conventional technique but was still considered accurate for predicting tensile properties. The DIC models also demonstrated good agreement with the experimental findings, suggesting its suitability as a straightforward evaluation method for predicting tensile properties. [ABSTRACT FROM AUTHOR]

The growing demand for low‐temperature thin‐film encapsulation (TFE) in advanced flexible and wearable organic light‐emitting diodes (OLEDs) has intensified to mitigate thermal issues, which deteriorate the device performance. Herein, Al2O3/TiO2 nanolaminates (A/T NLs)are introduced and fabricated via thermal atomic layer deposition at an exceptionally low temperature of 40 °C, which exhibited enhanced mechanical and environmental robustness. Compared to the single‐layer Al2O3 and TiO2 thin films (0.06% and 0.31%), the A/T NLs with sublayer thickness under 15 nm exhibit dramatic improvement in elongation (0.46–0.53%), attributed to the effective decoupling of critical defects by the Al2O3/TiO2 interfaces. Furthermore, the A/T NLs with 3 nm‐thick‐sublayer demonstrate highly improved water vapor transmission rates of 9.48 × 10−5 g m−2 day−1, making them promising candidates for TFE in wearable OLEDs. Notably, the optimized A/T NL‐encapsulated wearable phosphorescent OLEDs (phOLEDs) exhibit extended lifetimes (LT70), surpassing 200 h in the accelerated environmental conditions (40 °C/90% RH) which is 40 times longer lifetimes compared to the not encapsulated OLEDs. Additionally, the A/T NL‐encapsulated wearable phOLEDs displayed mechanical endurance, enduring 125 h even under the bending strain of 0.4% compared to the Al2O3‐ and TiO2‐encapsulated OLEDs (4 and 18 h). [ABSTRACT FROM AUTHOR]

AbstractThis study used human DNA structure to inspire an innovative design concept. Mechanical testing assessed how design parameters and thermal shock cycles affected it. As thermal shock cycles increase, material characteristics decrease. After sixty thermal shock cycles, tensile and flexural strengths dropped 43.33% and 35.90%, respectively. DNA structures had a better strength-to-weight ratio than solids. After 60 thermal shock cycles, 2 mm ribs, straight ribs, and hexagonal honeycomb ribs had higher tensile and flexural strengths of 9.42 and 20.76 MPa, respectively. [ABSTRACT FROM AUTHOR]

The current study focuses on the degradation rate of polypropylene (PP) and Bauhinia Vahlii (BV) fibers under soil burial and natural weathering conditions for 360 days. The BV‐PP composite was produced with varying BV fiber compositions (0, 10, 20, and 30 wt.%) and 3 % MAPP (Maleic Anhydride Grafted Polypropylene). In addition, MAPP is employed as a coupling agent to improve fiber‐matrix compatibility and promote degradation. The XRD examination shows that a 10 % BV‐PP composite has a crystallinity index of 52.05 %, which is higher than that of neat PP. The rate of biodegradability was investigated using weight loss and tensile properties. The largest degradation was seen in natural weathering conditions with 30 % composite showing the maximum weight loss of 3.8 % and loss in tensile strength and modulus of 16.76 % and 5.11 %, respectively. Simultaneously, no weight loss or drop in tensile characteristics was found in the case of neat PP over 360 days. The SEM images of soil burial show material deterioration, which may be aided by bacterial and fungal activity, whereas natural weathering conditions show a large crack, rougher fracture surface, and cavities, which are attributed to thermal stresses, changes in moisture content, and ultraviolet radiation, thereby promoting the degradation process. [ABSTRACT FROM AUTHOR]

Rapid evolution in engineering and manufacturing demands light weight material with enhanced mechanical properties. Aluminium metal matrix composites with ceramic reinforcement particulates serve this demand due to their reduced density, improved strength and hardness along with higher resistance to wear and corrosion. However, the material cost and reduced machinability hinders the full potential of utilization. To overcome these challenges, in this work cupola slag, an industrial waste generated as by product of cast iron production, has been incorporated as reinforcement of aluminium composites using low cost stir casting method. The enhancement of material properties and machinability by cupola slag inclusion on base alloy has been investigated in detail. Moreover, introspection about the underlying mechanisms responsible for the improvement in material properties has been studied using detailed microstructure and fractographic analysis. The results show improvement of in material properties and machinability up to 7 wt.–% cupola slag inclusion, beyond which the reduced wettablity prohibits sound castings. The ultimate tensile strength and specific strength observed to be improved by 18.20 % and 33.23 % respectively for 7 wt.–% slag reinforced composites when compared with base alloy. This work can be a successful addition to the knowledge pool of ongoing research on low‐cost novel material with enhanced properties. [ABSTRACT FROM AUTHOR]

To address the gap in research on the mechanical properties of peanuts in the harvesting period, the mechanical properties of peanut seedling vines, pods, and peduncles were studied during the peanut harvesting period. The moisture content of peanut pods, peduncles, and seedling vines was measured, yielding values of 36.03%, 66.76%, and 77.95%, respectively. The tensile characteristic parameters between the pods and peduncles, peduncles and peduncles, and the seedling vines and peduncles during the harvesting period were determined using an electronic universal testing machine at three different loading speeds: 10 mm/min, 20 mm/min, and 30 mm/min. The test results indicated that the peduncle–peduncle, peduncle–pod, and peduncle–seedling vine detachment forces were 19.91 N, 17.41 N, and 8.62 N. The mechanical properties of peanuts during the harvesting period differed from those of peanuts that were excavated and sun-dried. Peanut-digging and turning machines should be designed based on the detachment force required to separate the peduncles from the pods, which, at a loading speed of 20 mm/min, is 17 N. This examination of the mechanical properties of peanuts during the harvesting period could have significant practical implications and a lasting influence on enhancing the efficiency and quality of peanut harvesting, refining harvesting machinery design, and advancing agricultural modernization. [ABSTRACT FROM AUTHOR]

This paper was aimed to study the mechanical properties of Istle fibre composites. The process of fabrication was done by hand layup technique at three different fibre orientations i.e., unidirectional, bidirectional and 45 degrees inclined, and also its effect on tensile and flexural property that was studied in the Instron Testing Machine. The fibre volume ratio was kept uniform for the entire specimen as 50:50. The treatment of istle fibre was done with sodium hydroxide to increase the fibre matrix bonding. The effect of E-glass reinforcement has also been studied in both bending tests and flexural tests. The maximum tensile and bending modulus recorded were from unidirectional fibre specimen. [ABSTRACT FROM AUTHOR]

This work develops a polarization-dependent analytical model using terahertz time-domain spectroscopy (THz-TDS) for computing strain in materials. The model establishes a correlation between volumetric strain and the change in time of arrival for a THz pulse by using the dielectrostrictive properties, variations in doping particle density, and changes in the thickness of the sample resulting from Poisson's effects. The analytical model is validated through strain mapping of polydimethylsiloxane (PDMS) doped with passive highly dielectrostrictive strontium titanate (STO). Two experiments, using an open-hole tensile and a circular edge-notch specimen are conducted to show the efficacy of the proposed. The stress relaxation behavior of the composite is measured and accounted for to prevent changes in strain during the measurement window. The THz strain mapping results are compared with the finite element model (FEM) and surface strain measurements using the digital image correlation (DIC) method. The experimental findings exhibit sensitivity to material features such as particle clumping and edge effects. The THz strain map shows a strong agreement with FEM and DIC results, thus demonstrating the applicability of this technique for surface and sub-surface strain mapping in polymeric composites. [ABSTRACT FROM AUTHOR]

Tissue engineering is a set of techniques for producing or reconstructing tissue that primarily aims to restore or improve the function of tissues in the human body. The aim of the present study was to evaluate the mechanical and histological characteristics of decellularized tracheal scaffolds prepared in comparison with fresh trachea for use in tracheal repair. In order to prepare the scaffold, sheep's trachea was prepared and after cleaning the waste tissues, they were decellularized. Then decellularized scaffolds were evaluated histologically and laboratory and numerical study of the nonlinear mechanical behavior of tracheal tissue and scaffold and their comparison. Examining the results of histological evaluations showed that the decellularization of the scaffolds was completely done. These results were confirmed by hematoxylin–eosin staining. Also, the exact hyperelastic properties of tracheal tissue and scaffold were used in biomechanical models, and according to the presented results, the five-term Mooney–Rivlin strain energy density function became a suitable behavioral model for modeling the hyperelastic behavior of trachea and scaffold. In total, the results of this research showed that the scaffolds obtained from decellularization by preserving the main compositions of the desired tissue can be a suitable platform for investigating cell behaviors. [ABSTRACT FROM AUTHOR]

Featured Application: The mechanical properties of microperforated titanium sheets are studied in this work by experimental data and Finite Element Modeling. Hybrid Laminar Flow Control (HLFC) is a promising technology for reducing aircraft drag and, therefore, emissions and fuel consumption. The integration of HLFC systems within the small space of the wing leading edge, together with de-icing and high lift systems, is one of the main challenges of this technology. This challenge can be tackled by using microholes along the outer skin panels to control suction without the need for an internal chamber. However, microperforations modify the mechanical properties of titanium sheets, which bring new challenges in terms of wing manufacturability. These modified properties create uncertainty that must be investigated. The present paper studies the mechanical properties of micro-drilled titanium grade 2 sheets and their modeling using the Finite Element Method (FEM). First, an experimental campaign consisting of tensile and Nakajima tests is conducted. Then, an FEM model is developed to understand the role of the anisotropy in sheet formability. The anisotropy ratios are found by combination of Design of Experiments (DoE) and the Response Surface Method (RSM); these ratios are as follows: 1.050, 1.320, and 0.975 in the directions Y, Z, and XY, respectively. Some mechanical properties are affected by the presence of microholes, especially the elongation and formability that are significantly reduced. The reduction in elongation depends on the orientation: 20% in longitudinal, 17% in diagonal, and 31% in transversal. [ABSTRACT FROM AUTHOR]

In this study, we examined the fatigue crack nucleation and propagation mechanisms of an AlSi sputtered thin film subjected to the quasistatic tensile test and cyclic loading test by scanning electron microscopy. An AlSi thin film with 1.0 wt% Si was prepared by dc magnetron sputtering at a substrate temperature of 260 ℃, followed by annealing at 490 ℃. Two types of uniaxial tensile test equipment were prepared, namely, manual tensile loading equipment and automatic tensile loading equipment. The combination of the use of manual-type equipment and electron backscattered diffraction analysis enabled us to visualize crystal grain subdivision mechanisms. The automatic-type equipment enabled us to understand fatigue crack propagation mechanisms in the AlSi thin film after crack nucleation originating from grain subdivision. A fatigue crack propagated in a zigzag manner under the low stress amplitude condition during the fatigue test, whereas it propagated straightly under the high stress amplitude condition. This phenomenon is discussed from the viewpoints of crack detouring around Si segregates and Si brittleness. [ABSTRACT FROM AUTHOR]

The Gas Tungsten Arc Welding (GTAW) process is well-known for its accuracy, simplicity, and economical, making it the optimum method for joining Super Duplex Stainless Steel (SDSS) materials. This review paper investigates the influence of the GTAW process on the microstructure, tensile strength, micro-hardness and corrosion resistance of SDSS welded joints. The optimum constant current GTAW process parameters are discovered by various researchers who found that the welding current range should be 65A–160A for joining up to 6 mm thick SDSS material. The pulsed current GTAW process optimum Peak current range (120–165A) and back current (60–80A) range for joining 4–14 mm thick SDSS material. Microstructural analysis revealed that coarse grain is in the welded joint's weld zone (WZ) and heat-affected zone (HAZ) because of the weld thermal cycle. The Widmanstatten austenite with ferrite grain boundary is found between HAZ and WZ due to thermal cooling. Welded joint tensile strength (740 MPa–896 MPa) is sometimes greater or the same as the base metal. It shows the GTAW best parameters selection. The microhardness of HAZ (380 HV) and WZ (370 HV) of the welded joint is increased with respect to base metal (310HV) GTAW process. Multiple studies have shown that using the best GTAW parameters can improve the microstructural properties of SDSS, resulting in increased tensile strength. The charge transfer resistance analysis of GTAW welded joint revealed that higher charge transfer leads to a lower corrosion rate having ER2594 filler material with icorrs value of 0.0139 μA/cm2.

Abstract To develop a material with strong impact resistance, bending direction and in‐plane direction, the tensile and bending properties of sandwich films obtained by placing and re‐pressing a compression‐molded polypropylene sheet between two sheets of carbon‐fiber‐reinforced thermoplastics (CFRTPs) were evaluated. Three types of CFRTP were investigated, and thermoplastic nylon 66, polyurethane, and polyphenylene sulfite were used as the resin base materials to wrap the carbon fiber. Regarding the tensile properties of the sandwich films, the Young's modulus and maximum stress values were lower compared with those of the CFRTP sheets, regardless of the resin base material. However, improvements in elongation properties of 97%, 109%, and 156%, respectively were found, transforming the film into a softer and stronger film. Regarding the bending properties of the sandwich films, the Young's modulus and maximum stress values were higher compared with those of the CFRTP sheet. To examine the influence of the number of layers, the five‐layer sheet, in which the sandwich film was placed in two CFRTP sheets, exhibited inferior elongation properties to the three‐layer sheet during the tensile test. However, the results of the bending test found a significant improvement in Young's modulus of approximately 2.5 times and final strength of approximately three times. We anticipate that this material could be applicable to components requiring specific mechanical properties in both bending and in‐plane directions in future applications. Highlights CFRTP sandwich sheets were fabricated using a simple hot‐press method. The sandwich sheet showed improved mechanical properties in the in‐plane directions. Both the tensile modulus and the bending modulus have reached the GPa‐order. The sandwich film in question had particularly excellent bending properties. The sandwich film showed dependence on the number of layers. In‐plane elasticity of the films was evaluated using a falling ball test.

INTRODUCTION. Fluoroquinolones are antibacterial agents associated with adverse drug reactions (ARDs), including aortic lesions; this ARD risk limits the use of fluoroquinolones. Moreover, fluoroquinolones have been reported to induce lesions in other connective tissues (cartilage, tendons), associated with magnesium deficiency.AIM. The study aimed to analyse the effects of magnesium orotate on the thoracic aorta in laboratory rabbits treated with levofloxacin.MATERIALS AND METHODS. The study randomised laboratory rabbits into 3 groups of 10 animals each to receive oral doses of either the carrier solution (control group), or 150 mg/kg/day levofloxacin (levofloxacin group), or 150 mg/ kg/day levofloxacin and 140 mg/kg/day magnesium orotate (levofloxacin/magnesium group). After 14 days of treatment, venous blood samples were taken to determine the serum levels of magnesium, matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), as well as MMP-9 to TIMP-1 ratios. The authors conducted morphological and mechanical characterisation of thoracic aorta samples; the mechanical characterisation involved uniaxial tensile testing. Data are presented as the mean and standard deviation values.RESULTS. The study did not detect any changes in the serum MMP-9, TIMP-1, and magnesium levels or in the MMP-9/TIMP-1 ratios. The authors identified foci of moderate elastic fibre fragmentation in the aortic media in 5 of 10 aortic samples from the levofloxacin group, in 1 of 10 samples from the levofloxacin/magnesium group, and in none from the control group (p=0.013). Rabbits from the levofloxacin group had significantly fewer medial elastic membranes than the others (p=0.015; vs the control group: p=0.022), and their elastic mem

To address the gap in research on the mechanical properties of peanuts in the harvesting period, the mechanical properties of peanut seedling vines, pods, and peduncles were studied during the peanut harvesting period. The moisture content of peanut pods, peduncles, and seedling vines was measured, yielding values of 36.03%, 66.76%, and 77.95%, respectively. The tensile characteristic parameters between the pods and peduncles, peduncles and peduncles, and the seedling vines and peduncles during the harvesting period were determined using an electronic universal testing machine at three different loading speeds: 10 mm/min, 20 mm/min, and 30 mm/min. The test results indicated that the peduncle–peduncle, peduncle–pod, and peduncle–seedling vine detachment forces were 19.91 N, 17.41 N, and 8.62 N. The mechanical properties of peanuts during the harvesting period differed from those of peanuts that were excavated and sun-dried. Peanut-digging and turning machines should be designed based on the detachment force required to separate the peduncles from the pods, which, at a loading speed of 20 mm/min, is 17 N. This examination of the mechanical properties of peanuts during the harvesting period could have significant practical implications and a lasting influence on enhancing the efficiency and quality of peanut harvesting, refining harvesting machinery design, and advancing agricultural modernization.

Micro plasma arc welding (MPAW) is frequently used for joining thin sheets of ferrous and nonferrous materials. In this study, austenitic stainless steel 316L of 0.5 mm thin sheets are joined by using MPAW. The weld metallurgy is characterized by field electron scanning microscopy (FESEM), Transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques to evaluate different phases formation and their orientation in detail. Mechanical tests like tensile test, micro hardness test is also carried out to measure the joint quality. It is found that the weld joint is constituent of two major phases, δ-ferrite and austenite (γ), and few secondary phases like chromium carbides. The ferrite percentage in the fusion zone is higher than the as received base material. The fusion zone hardness is increased due to the presence of high amount of ferrite and carbides. The tensile fracture surface contains lots of dimples and voids, which indicates good ductility of the joint. A defect free and good joint efficiency is achieved by using MPAW.

An arc is used as a heat source in the manufacturing process known as wire arc additive manufacturing (WAAM), which uses layer-by-layer cladding to fuse wire. In the current work, Wire Arc Additive Manufacturing (WAAM)-fabricated Inconel 625 alloy has been examined. The research was done on the microstructure, mechanical characteristics, and impact of the solidification rate on the characteristics of the manufactured specimens for the Inconel 625 alloy. Microstructural analysis has shown that the specimen’s layers have varying microstructures. The bottom layer exhibits a blocky or equiaxed microstructure because of the faster solidification rate, while the upper zone generated elongated and discontinuous dendrites because of the slower solidification rate. This difference in the microstructure in the top and bottom zones directly influence the ultimate tensile strength, where the bottom zone has more tensile and yield strength than the top zone. Also, the presence of cracks in the top zone, which is found during the fractography test, also correlated the top zone’s ultimate tensile strength.

This study systematically investigates the effects of high-power continuous wave laser (CWL) treatment on the mechanical behavior and failure mechanisms of SM400A steel, comparing these outcomes with those of untreated specimens. The findings reveal that while CWL treatment enhances surface hardness, it has minimal impact on the strength of thick structural steel components. However, excessive laser energy density leads to surface defects and softening of the microstructure, adversely affecting the material's toughness. This results in a reduction in elongation at fracture, transitioning the failure mode from ductile to brittle. The study concludes that to ensure the safe use of laser-treated structures, the laser energy density should be carefully controlled not to exceed 3000 J/cm2.

This research aims to examine the physical, structural and chemical properties of Aster Squamatus (AS) fibres, which are commonly found in Algeria, Brazil, France and the West Indies. In this work, we assess their appropriateness as reinforcing fillers to fabricate components for polymer composites principally designed for lightweight applications. To accomplish this objective, an extraction of fibres from plants modification of AS fibres and characterization of both untreated fibres (UASFs) and alkali-treated AS fibres (TASFs) are conducted. We analysed the crystallinity, chemical composition, thermal characteristics, and mechanical properties of AS fibres as per standard methods. It's clear from chemical treatment that amorphous components were successfully eliminated from the AS fibres, including hemicellulose, lignin, and wax. Consequently, the fibres' thermal, physical, and mechanical characteristics including Young's modulus, tensile strength, crystalline index, and surface roughness were substantially enhanced. It was determined that the fibres possessed a thermal stability of around 250 °C, with the maximal degradation temperature rising from 372.50 to 375.35 °C. The maximum stress rose from 183.24 ± 25.27 to 302.00 ± 24.91 MPa, the Young's modulus increased from 11.08 ± 1.1 to 18.53 ± 1.45 GPa, and the crystallinity index increased from 43% to 45%. Two-parameter Weibull statistics showed a strong link between experimental data and mechanical features of the twenty samples. We concluded from this work that AS plant fibres can serve as a robust reinforcing material in polymer composites for various applications.

Additive manufacturing is widely used to fabricate metamaterials. The mechanical properties of these are tailored by modifying topological parameters to meet desired performance. Here, an auxetic metamaterial composed of arc-shape elements is presented. The directional dependency of the apparent stiffness was characterized through finite element analysis and tensile and compressive tests on additively manufactured samples with fused filament fabrication in thermoplastic polyurethane. Poisson's ratio was measured with computational vision. The effective Young's modulus resulted with a nonlinear relation to the wall thickness. The orientation sensibility exposed the relevance of rotational symmetry in a lattice architected metamaterial. [ABSTRACT FROM AUTHOR]

The bonding performance and formation of the interphase region between fiber and matrix have significant effects on the strength and durability of composites. A new approach, involving combined experimental and numerical analyses, has been developed to avoid the shortcomings and scattering associated with local experimental methods. For this purpose, tensile tests are performed on specimens fabricated from a single glass fiber and epoxy resin. The elongations for specified lengths are measured using the digital image correlation (DIC) technic. The size of the fiber diameter and specimen section are also measured from SEM images. The obtained experimental displacements for micro tensile tests are used in an inverse elastic finite element solution to obtain the interphase elastic modulus. It is shown that, considering the interphase thickness of 1.0 μm that is more realistic, the interphase elastic modulus is in the range of 12 ∼ 19 GPa. However, the performed sensitivity analysis shown that considering interphase thickness ranging from zero to 2.0 μm the interphase elastic modulus varies between 9 and 46 GPa. It is shown that the proposed procedure can be used to obtain the overall mechanical properties of the matrix/fiber interphase in long fiber composites. [ABSTRACT FROM AUTHOR]

A mechanical performance of synthesizedunsatured polyester (UP) composite reinforced by OleaEuropea var. Sylvestris fibers was studied by applying the complete 23 factorial plan of experience. The variables orientation angle (V1), length (V2) and ratio (V3) of these fibers have been investigated. The experimental design was used to evaluate these factors on the Young's modulus and the maximum stress. The textural properties of the fibers were highlighted by XRD, SEM, EDS and FTIR. According to the experimental designresults, the V1 and V2 factors are the most influential and the V1V2/V2V1 and V1V3/V3V1 interactions are the most significant. The significance Student's tests of all effects were found non negligible and significant and the validation of the proposed linear models was verified by using analysis of variance (ANOVA). The study of the fracture facies of specimens of various experimental configurations by SEM showed the direct dependence of factors V1, V2 and V3 and their interactions on the improvement of the mechanical properties. Five deterioration zones were detected and identified as matrix cracking, longitudinal intra fiber cracking, fiber-matrix decohesion, fiber-matrix loosening and strong fiber-matrix cohesion. [ABSTRACT FROM AUTHOR]

Under the conditions of deep high stress, weak surrounding rock, and strong mining influence, the surrounding rock of deep-buried roadway frequently experiences large deformations, the controllability of large deformation support for this type of surrounding rock is generally poor, and the conventional anchor bolts often break or fail to anchor due to their low elongation rate, which cannot adapt to the large deformation of the roadway, resulting in the risk of roof caving in the roadway. The constant resistance device by using composite expansion pipe (CRD-cep) used in conjunction with cable bolt has been invented. The main structures include a stop end cover, an expansion pipe, an integrated tray and a conical lock. The conical lock overcomes the approximately constant composite resistance generated by the “expansion grinding” of the expanding pipe, thus, the constant resistance of the cable bolt during the large deformation process of the surrounding rock is achieved. The mechanical characteristics and working stability of the resistance stabilizer are improved by theoretical analysis, numerical simulation and static tensile testing and other comprehensive research methods, and the influence of the expansion increment and lock cone angle of the composite expansion tube constant resistance device on the deformation of the expansion pipe and the composite resistance of the CRD-cep has been understood. The test results indicate that the composite resistance of the CRD-cep is mainly divided into two processes: the fast rising resistance stage and the near constant resistance stage, and the nearly constant resistance section as the main stage reaches 85% to 90% of the entire test process. The lock cone angle and expansion increment directly affect the deformation of the expansion pipe and the mechanical characteristics of the CRD-cep. When the lock cone angle is less than 20°, the deformation of the expanding pipe is uniform and the composite resistance of the CRD-cep is stable. The expanding increment determines the size of the CRD-cep. The required constant resistance of the cable bolt can be obtained by adjusting the expanding increment. When the diameter of the anchor rope used is 17.8 mm, the lock cone angle is 15° and the expansion increment is 5 mm, the constant resistance of the CRD-cep is about 265.92 kN, when the diameter of the anchor rope used is 21.8 mm, the lock cone angle is 15° and the expansion increment is 8 mm, the constant resistance of the CRD-cep is about 424.15 kN, and the working state is stable and reliable, which can better meet the constant resistance support requirements of large deformation roadway. The CRD-cep has the characteristics of strong working stability, adjustable constant resistance stroke and resistance, simple structure, and convenient installation, which is an effective supplement to the control technology of surrounding rock in large deformation roadway.

Combining a preheating source with conventional arc welding is a promising method to study the weld quality and improvement of strength for high-strength super-alloy materials. The present research used an induction preheating source with plasma arc welding (PAW) to weld Inconel 625 thick plates. The investigation was performed at a constant induction current of 600 A, welding speed of 100 mm/min and a plasma welding current of 135 A. The induction-assisted plasma arc welding (IAPAW) demonstrated that a weld joint was possible with static induction preheating and a high plasma welding current at low welding speed. The microstructural observation showed various dendritic structures in the fusion zone (FZ). The FESEM and EDX analysis confirmed the formation of Laves phase in the interdendritic structure of the FZ. The ultimate tensile strength of the IAPAW joint reached to 658 MPa. The tensile fracture surface of the welded sample revealed a lower number of dimples, indicating the reduction of ductility. The XRD analysis was carried out at various zones and it confirmed the peak shifting towards the higher 2-theta value of the FZ.

This study evaluated the properties of 3D-printed Onyx–fiberglass composites. These composites were 3D-printed with zero, one, two, three, and four layers of fiberglass. Ten samples of each configuration were printed for the tensile and flexural tests. The average tensile strength of the Onyx specimens was calculated to be 44.79 MPa, which increased linearly by approximately 20–25 MPa with each additional fiberglass layer. The elastic moduli calculated from the micromechanics models were compared with the experimental values obtained from the tensile tests. The experimental elastic modulus increased more significantly than the model prediction when more fiberglass layers were added. The flexural modulus of Onyx was 17.6 GPa, which increased with each additional fiberglass layer. This quantitative analysis of composites fabricated using 3D printing highlights their potential for commercialization and industrial applications. [ABSTRACT FROM AUTHOR]

Optoelectronic components are crucial across various industries. They benefit greatly from advancements in 3D printing techniques that enable the fabrication of intricate parts. Among these techniques, Material Extrusion (MEX) stands out for its simplicity and cost-effectiveness. Integrating 3D printing into production processes offers the potential to create components with enhanced electrostatic discharge (ESD) resistance, a critical factor for ensuring the reliability and safety of optoelectronic devices. Polyethylene terephthalate glycol-modified (PET-G) is an amorphous copolymer renowned for its high transparency, excellent mechanical properties, and chemical resistance, which make it particularly suitable for 3D printing applications. This study focuses on analyzing the mechanical, structural, and electrostatic properties of pure PET-G as well as PET-G doped with additives to evaluate the effects of doping on its final properties. The findings highlight that pure PET-G exhibits superior mechanical strength compared to doped variants. Conversely, doped PET-G demonstrates enhanced resistance to electrostatic discharge, which is advantageous for applications requiring ESD mitigation. This research underscores the importance of material selection and optimization in 3D printing processes to achieve desired mechanical and electrical properties in optoelectronic components. By leveraging 3D printing technologies like MEX and exploring material modifications, industries can further innovate and enhance the production of optoelectronic devices, fostering their widespread adoption in specialized fields. [ABSTRACT FROM AUTHOR]

During tensile testing of materials, strain measurement is conducted using either contact or non-contact methods. Contact methods offer high accuracy and precision but are limited by the specimen's thickness and dimensions, whereas non-contact methods minimize damage to thin specimens and allow measurements in various environments, though they require longer preparation and calculation times. This paper proposes a circular grid marking pattern and a strain prediction algorithm using artificial intelligence (AI), which simplifies the preparation process and allows strain prediction without additional equipment. The circular grid pattern can be arranged in various configurations from 1 × 5 to 5 × 7, and a laser marker, which requires minimal time, was used to engrave the pattern on the specimen to shorten the preparation time. The AI model, trained on image-based data, enables strain calculation regardless of the specimen's gauge length and size, and allows measurement of local strain as well as gauge-length strain. The reliability of this concept was verified by applying it to tensile testing. [ABSTRACT FROM AUTHOR]

To study the service performance of polymer bilayer sheets, this experimental study focuses on the thermal and mechanical characterization of sheets composed of two polymer layers (named ABS/PMMA), an Acrylonitrile–Butadiene–Styrene layer and a 15% Poly(Methyl Methacrylate) layer. These sheets are used in many industrial components subjected to thermal and mechanical strain. The studied bilayer sheets were obtained by a co-extrusion process. Thermal properties were measured through Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Mechanical behavior was determined via uniaxial tensile tests at various temperatures less than the glass transition temperature and using two strain rates of 3.33 × 10−4 s−1 and 1.66 × 10−2 s−1. Furthermore, the viscoelastic properties are determined via Dynamic Mechanical Analysis (DMA) using two frequencies. The findings revealed substantial ABS/PMMA bilayer thermal stability. The obtained glass transition temperature of this bilayer was 111 °C. Its viscoelastic behavior was described by determining the storage and loss modulus. Furthermore, the influence of temperature and strain rate parameters on the tensile behavior of the ABS/PMMA bilayer was also determined showing high dependence of mechanical behavior on these two parameters. This bilayer exhibits brittleness at room temperature and high total strain exceeding 62% at 90 °C. [ABSTRACT FROM AUTHOR]

In this study, basic research was conducted to develop numerical models for filling behavior, compaction process, and tensile test of compacts. Numerical calculations of the filling behavior using distinct element method were performed. The calculated results got a good agreement with experimental one, enabling us to perform the numerical analysis of the filling process. The powder compaction process was also performed using multi particle finite element method (MP-FEM) with the information on the particle position and radius obtained from the DEM calculations. The compaction pressures of the same order as the experimental results were obtained, suggesting that the powder compaction process was successfully analyzed numerically. Furthermore, using the compact geometry obtained from the compaction calculations, tensile tests were numerically calculated using the MP-FEM when a load was applied in the radial direction of the compact. The crushing process of the powder layer was successfully represented. It was shown that the tensile strength can be calculated from the numerical analysis. The particle filling behavior using DEM and the compaction and crushing processes using MP-FEM were successfully calculated numerically in a series. [ABSTRACT FROM AUTHOR]

The purpose of this research is to experiment with different weight percentages of nanoB4C (5%, 10%, and 15%) in order to develop nano B4C/graphite-reinforced AA7075 alloy composites. An analysis of the morphological and mechanical behavior of the material was carried out using SEM in accordance with ASTM E8, E9, E23, and D790. All of the reinforcement particles are distributed uniformly throughout the matrix alloy, and there are no porous portions left over. Composite materials have a hardness of 30.18 percent, an ultimate tensile strength that is 40.93 percent higher, and a compressive strength that is 19.73 percent higher than the base material. The flexural strength of the material is improved by 26.75% when the matrix dislocation density and elastic modulus fluctuations are higher. There was a 66.21% increase in impact strength as a result of reduced porosity and grain refinement. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental study to investigate the effects of two types of graphene, dried (DG) and hydrated graphene (HG), when enhancing the interfacial and tensile mechanical properties of fabric-reinforced cementitious matrix (FRCM) composites. The inclusion of DG and HG could produce an improvement in the tensile strength of the FRCM composites by increasing the tensile strength of the mortar paste and the amount of fibers that participate in load bearing due to the increased penetration of mortar (cement hydrates) into the fiber bundle. The better dispersion of HG produces better results than DG. The maximum increases in the overall tensile strengths of the FRCM composites with DG and HG are 18% and 31%, respectively, with the majority of these improvements coming from the increase in the number of fibers that participate in load bearing. The microstructure images indicate increases of up to 20% and 44% in the mortar penetration thickness into the fiber bundles using DG and HG, respectively. [ABSTRACT FROM AUTHOR]

The additive manufacturing (AM) is a relative new manufacturing process that belongs to the fourth industrial revolution, thus yielding new challenges that are worth the study in terms of reliability. In that sense, this work presents a comparative study of as printed and optimally heat-treated 1.2709 maraging steel manufactured by laser powder bead fusion (LPBF) AM process. The results suggest that parts were sound in terms of visual inspection and microstructural analysis. In the case of mechanical properties, the results suggest that the highest variability occurred after the heat treatment. The high cycle fatigue samples revealed a fracture without exhibiting a considerable amount of plastic deformation. On the other hand, the low cycle fatigue results revealed that at 1% strain the optimally heat-treated specimens have lower fatigue life due to the presence of surface discontinuities and the reduction of ductility after the heat treatment. [ABSTRACT FROM AUTHOR]

Commercially pure aluminum alloy, AA1100, presents good electrical and thermal conductivity, high formability, and low cost. Those favorable characteristics have the potential to enable bipolar plates with improved economics and enhanced performance compared to current stainless steel bipolar plates for proton exchange membrane fuel cells. An accurate constitutive model is essential to develop and optimize processing parameters and effectively control the forming process. The objective of this work is to develop a constitutive model of AA1100 that is able to simulate stress-strain relation, formed geometry, and predict the onset of fracture strain to avoid forming failure. Initially, a set of tensile tests at temperature between 300 and 500 °C and strain rate between 0.005 and 1.0/s were conducted to examine the deformation behavior. Then, a set of damage-based unified viscoplastic constitutive equations is proposed and calibrated based on the results of stress-strain data. A genetic algorithm optimization method is applied to search for best fitting material constants in constitutive equations. The proposed model shows good predictability of both the stress-strain relation and fracture strain at low strain rate and high-temperature conditions. The accuracy of proposed model is also evaluated statistically. A comparison of the proposed model with three popular models (Arrhenius-type model, Johnson-Cook model, and Zerilli-Armstrong model) was made. The proposed model shows the best experimental agreement with correlation coefficient of 0.96 in contrast to 0.25, 0.38, and 0.75 for the popular models, respectively. The proposed model can help to optimize the elevated temperature forming process and guide die design to enable optimal geometric features in the formed components. [ABSTRACT FROM AUTHOR]

An arc is used as a heat source in the manufacturing process known as wire arc additive manufacturing (WAAM), which uses layer-by-layer cladding to fuse wire. in the current work, wire arc additive manufacturing (WAAM)-fabricated inconel 625 alloy has been examined. The research was done on the microstructure, mechanical characteristics, and impact of the solidification rate on the characteristics of the manufactured specimens for the inconel 625 alloy. Microstructural analysis has shown that the specimen's layers have varying microstructures. The bottom layer exhibits a blocky or equiaxed microstructure because of the faster solidification rate, while the upper zone generated elongated and discontinuous dendrites because of the slower solidification rate. This difference in the microstructure in the top and bottom zones directly influence the ultimate tensile strength, where the bottom zone has more tensile and yield strength than the top zone. Also, the presence of cracks in the top zone, which is found during the fractography test, also correlated the top zone's ultimate tensile strength. [ABSTRACT FROM AUTHOR]

Micro plasma arc welding (MPAW) is frequently used for joining thin sheets of ferrous and nonferrous materials. In this study, austenitic stainless steel 316L of 0.5 mm thin sheets are joined by using MPAW. The weld metallurgy is characterized by field electron scanning microscopy (FESEM), Transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques to evaluate different phases formation and their orientation in detail. Mechanical tests like tensile test, micro hardness test is also carried out to measure the joint quality. It is found that the weld joint is constituent of two major phases, δ-ferrite and austenite (γ), and few secondary phases like chromium carbides. The ferrite percentage in the fusion zone is higher than the as received base material. The fusion zone hardness is increased due to the presence of high amount of ferrite and carbides. The tensile fracture surface contains lots of dimples and voids, which indicates good ductility of the joint. A defect free and good joint efficiency is achieved by using MPAW. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of copper nanoparticles and graphene oxide nanosheets on the tensile properties and impact strength of epoxy-based hybrid nanocomposites. A mechanical mixer and an ultrasonicator were used to mix the reinforcements with the epoxy resin. Field Emission Scanning Electron Microscope (FE-SEM) was used to examine the fracture surface morphology, and tensile and impact tests were conducted to assess the mechanical properties of the nanocomposites. These properties were optimized by a genetic algorithm. The results showed that adding 0.75 wt% copper nanoparticles and 1 wt.% graphene oxide to the epoxy increased its tensile strength by 45.7 and 37.14%, respectively, compared with those of pure epoxy, and adding 0.5 wt% graphene oxide and 0.75 wt% copper nanoparticle led to a 61.76 and 32.35% increase in its fracture strength. The tensile test results indicated that the tensile strength of specimens reinforced with 0.125 wt% graphene oxide and 0.125 wt% copper nanoparticles increased by 47.51% compared with those of pure epoxy and adding 0.375 wt% graphene oxide and 0.375 wt% copper nanoparticles increased the fracture energy by 91.18%. [ABSTRACT FROM AUTHOR]

One of the most frequent causes of coal fired power plant shutdown is boiler tube leak. Superheaters are crucial components of boilers operating under high temperatures and pressures. Understanding the superheater potential damages is essential to define the rectification action needed to keep and elevate overall power plant productivity. This paper highlights the analysis of platen superheater tube failure in a 2x150 MW coal-fired power plant in South Sumatera. Various test including chemical composition, hardness, tensile, metallography, SEM fracture surface examination, and XRD compound analysis were conducted for investigation purposed. The failure was initiated by the plugging of the tube elbow due to deposits and ashes adhering to the tube's interior. This obstruction prevented saturated steam flow inside the tube, leading to overheating and a subsequent drop in mechanical strength. Overheating was confirmed by the presence of spheroid particles in the ferrite matrix. Prolonged overheating resulted in the formation of microvoids, leading to creep failure and crack formation in the tube. The improvements made by adding refractory material give positive results. The platen superheater tubes which previously exceeded temperature limits, currently operate within normal range temperatures, reduced spray water consumption 6-10 tons/day, and significantly increased boiler efficiency from 83.19% to 83.54%. [ABSTRACT FROM AUTHOR]

This study evaluated several composite materials in detail in order to optimize below-knee prosthetic sockets. Extensile and fatigue testing yielded valuable information about each group's mechanical characteristics. The yield stress, ultimate stress, and modulus of elasticity (E) in the perlon group (Group A) were determined to be 10.216 MPa, 38.046 MPa, and 1.14 GPa, respectively. However, with a modulus of elasticity (E) of 2.55 GPa, a yield stress of 90.23 MPa, and an ultimate stress of 103.177 MPa, the carbon fiber group (Group B) showed noticeably improved mechanical characteristics. Finally, the glass fiber group (Group C) showed a modulus of elasticity (E) of 1.17 GPa, a yield stress of 31.862 MPa, and an ultimate stress of 42.934 MPa. The results demonstrated carbon fiber's significant influence on material performance. Carbon fiber fatigue showed better fatigue resistance than perlon, highlighting the longer lifespan of carbon fiber-based sockets. Interestingly, ambient temperature was used for all of the testing. The interface pressure study reveals that the lateral side (560 kPa) and rear side (564 kPa) have the highest recorded values. This demonstrates that the pressure was evenly distributed throughout the tissue and away from the bony parts, improving patient comfort and being compatible with the suspension's dynamics and the user's comfort when walking. The safety factor results for Groups A and C raised questions and pointed to possible design flaws. Group B, on the other hand, showed generally satisfactory safety standards, above 5 for most of the socket area, with a minor section below 5 indicating potential for improvement. The stress distribution for groups stayed below 2.5 MPa and below 10 MPa. [ABSTRACT FROM AUTHOR]