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The addition of fillers to polymer composites induces a positive influence on the mechanical and tribological properties of the hybrid composites. These properties can be validated for possible uses such as automobile, construction, shipping, aerospace, sports equipment, electronics, and biomedical domains. In the present research, epoxy matrix reinforced with nylon-6 fibers and glass fibers were prepared using the solution blend technique. Alumina nanoparticles are added as fillers to enhance the properties of epoxy hybrid composites. The large surface area of interaction of nanofillers exhibits better adhesion between matrix and fibers of composites, and it significantly affects the various properties of composites. The tribological characteristics of fabricated epoxy hybrid composites were evaluated under various parameters and conditions. The results revealed that the addition of nanofiller significantly reduces the wear loss of epoxy hybrid nanocomposites. The wear resistance of epoxy hybrid composites increased with increase in addition of nanofiller up to 1.0%, and it slightly decreased with the further addition of filler. The Taguchi analysis was carried out for the least coefficient of friction and specific wear rate. The analysis found that the specific wear rate and coefficient of friction mainly depend on load, followed by speed and nanofiller. The fractured and worn surface of Al2O3-filled epoxy hybrid composites was analysed using SEM. [ABSTRACT FROM AUTHOR]

In this research, synthesis and assessment of the mechanical and wear possessions of Al7049-nano B4C composites are determined by experiments. Using the liquid metallurgy route, a stir casting technique was used to create composites with increasing concentrations of nano B4C from 3 to 9 weight %. Each composite's reinforcement particles were heated to 400 degrees Celsius before being added to the molten Al7049 alloy in two separate steps, i.e., two-stage stir casting to optimise wettability and distribution. Scanning electron microscopy (SEM) was utilised to examine the microstructure, and energy dispersive spectroscopy (EDS) was utilised to determine the elemental make-up. Mechanical characteristics of composites were determined by subjecting them to tensile, compression, and hardness tests. Wear tests were conducted as per ASTM G99 standards with varying loads and speeds. Nanosized B4C particles were found to be dispersed throughout the sample space in a microstructural analysis. Hardness, ultimate strength, yield strength, and compression strength of Al7049 alloy composites were found to increase significantly as the weight percentage of nano B4C was increased. Additionally, compared to the unreinforced form, the ductility of the Al7049 alloy composites was slightly reduced. SEM micrographs of tensile-fractured specimens were used for research into the field of tensile fractography. Nano B4C reinforced composites exhibited superior wear resistance as compared to Al7049 alloy. These prepared composites can be used for wing root fitting of an aircraft. [ABSTRACT FROM AUTHOR]

Highlights: [•] The spring back and thinning effect during L-bending was determined on aluminum sheet. [•] Beyond a particular clearance, the above said effects are linearly increasing. [•] Below the critical clearance scratches will occur on the surface due to wear. [•] As the clearance reduces, the wear rate increases on the punching surface. [Copyright &y& Elsevier]

To keep up with the growing demand for composites in fields like medicine, transportation, safety, and athletics, researchers constantly create new composites. These experiments examined the impact of boron carbide filler particles in epoxy by making composites out of Lapox L-12 epoxy with 5, 10, and 15 percent boron carbide fillers using the hand layup technique. The mechanical properties of the prepared composites were measured as per ASTM standards, including hardness, ultimate tensile strength, yield strength, elongation, and flexural strength. Further, wear behavior of prepared composites was evaluated as ASTM G99 standard with varying loads and speeds. Hardness, tensile and flexural strength were increased with a slight decrease in percentage elongation after boron carbide filler particles were added to epoxy Lapox L-12. Lapox L-12 with boron carbide fillers reinforced composites were shown an improvement of 56.4% in hardness, 52.5% in ultimate strength and 25.85% improvements in the flexural strength. The wear behaviour of epoxy and its composites were affected by applied load and speeds. However, Lapox L-12 with boron carbide fillers reinforced composites exhibits higher wear resistance with smooth worn surface morphologies. The improvement in the tensile and wear behavior of L-12 epoxy with B4C composites can be utilized for several applications like air intake duct and air intake lip of an aircraft. [ABSTRACT FROM AUTHOR]

The Instrumented Charpy impact test is a promising method for determining a material's impact response. Stainless steel has a higher impact energy absorption capacity, high tensile, and yield strength compared to aluminum. Performance varies among grades; for instance, Aluminum 7075-T6 exceeds Aluminum 6061-T6 in tensile and yield strength. However, information regarding their energy capacity and impact signal pattern is lacking. This study investigated the impact properties using a Charpy machine, a data acquisition system, and a sensing element. Strain gauges were used to record the impact strain signal, enabling the analysis of impact duration, maximum strain, and the area under the curve. Specimens experimented include Stainless Steel 304, Aluminum Alloy 6061-T6, and Aluminum Alloy 7075-T6. The Charpy machine measures absorbed energy, while the theoretical impact energy is computed from software data. The area under the strain-time curve reflects the material's energy absorption capacity. Stainless Steel 304 demonstrates superior energy absorbed, impact duration, and area under the curve, followed by Aluminum 6061-T6 and Aluminum 7075-T6. Despite higher tensile and yield strength, the inferior impact response of Aluminum 7075-T6 highlights the importance of factors like ductility, elongation, and alloy composition. Consequently, Aluminum 6061 is commonly used in the automotive industry, while Aluminum 7075 is preferred in aerospace applications. [ABSTRACT FROM AUTHOR]

The main aim of this study was to produce hybrid metal matrix composites (HMMCs) using the stir casting method, by integrating different ceramic particles in a 3:2 ratio. The results of the scanning electron microscope (SEM) study revealed a uniform distribution of the reinforcing particles throughout the matrix of the hybrid metal matrix composites (HMMCs). The existence of these reinforcing particles inside the matrix was further confirmed using X-ray diffraction (XRD). The Al2618 alloy exhibited a significant reduction in its ultimate tensile strength (UTS), reaching a minimum value of 43% within the temperature range spanning from 50 to 300 °C. In contrast, the inclusion of boron carbide (B4C) and graphite (Gr) particles consistently improved the ultimate tensile strength (UTS) of Al2618-HMMCs. It was seen that Sample S4(12 wt% B4C and 8 wt% Gr). exhibited a notably enhanced ultimate tensile strength (UTS) performance, displaying a 15.8% increase. The present composition has promise for use in applications requiring high temperatures. [ABSTRACT FROM AUTHOR]

Star fruit (Averrhoa carambola L.) is an underutilized fruit grown in India, China, the US, and some regions of Africa. It is referred to as star fruit, due to its distinctive star shape and rich golden color. It has a wealth of essential nutrients and offers tremendous health advantages. In the present study, star fruit jaggery jelly of favorable physico-chemical and textural qualities was developed using the response surface method as the optimization technique for the ingredients. Jaggery, citric acid, and pectin were chosen as the three independent variables in a central composite design. At a constant fruit weight of 100 g, sample processing was carried out at five levels of citric acid (0.3–0.5%), pectin (0.5–1%), and jaggery (40–60%). The findings revealed that jaggery has a significant effect while citric acid and pectin did not affect the physico-chemical properties of star fruit jaggery jelly. At 54.00% jaggery, 0.82% pectin, and 0.47% citric acid the optimal production point for mass production was obtained. Jaggery concentrations of 50% and 60% had the requisite textural characteristics. For the production of extremely palatable star fruit jaggery jelly, the findings of the organoleptic evaluation showed that the jelly should contain 40–50% jaggery, 0.5–1% pectin, and 0.3–0.5% citric acid. [ABSTRACT FROM AUTHOR]

Bending operation is a very popular operation in the field of sheet metal forming. In bending operations several problems are encountered, springback is a very critical defect among them. In this research paper, effect of punch radius and sheet setting on the springback of AA1050/SS430 laminated sheet has been investigated. It has been found that punch radii and setting conditions have great influence on the prediction of springback. The study shows that the springback values can be decreased by decreasing the punch profile radius. Selecting appropriate sheet placing arrangement of 2-ply laminated sheets springback can fairly be controlled. A good agreement has been established between simulation and experimental results. [ABSTRACT FROM AUTHOR]

In large- or small-scale industries, machines have rotary element supported by bearings for accurate drive and fixed support. Fault diagnosis has gained much importance in recent times due to increased bearing failures. This demands an efficient diagnosis methodology to detect faults in bearings. In this work, fault diagnosis for the acquired vibration signals of healthy and fault seeded in rolling element bearings were investigated using signal processing technique and online machine learning approach. The research work is carried out in two phases. The first phase of research work investigates fault detection of bearing using conventional signal processing techniques such as time domain analysis and spectrum analysis. The results show that signal processing techniques may be useful for revealing post fault detection information. It was also concluded that the use of different signal processing techniques is often necessary to achieve meaningful diagnostic information from the signals. The second phase of research work describes fault diagnosis of bearing using machine learning approach. Using MATLAB, Discrete Wavelet Features (DWT), were extracted from acquired signals for different rolling element bearing conditions. J48 algorithm was implemented to extract most significant features. Extracted features were used as input to different classifiers to obtain maximum classification accuracy of rolling element bearings. The results showed that machine learning technique could be used to detect and classify the different fault sizes effectively with vibration signals. [ABSTRACT FROM AUTHOR]

The use of natural fiber-reinforced polymer composites has increased over a period of time, majorly due to the ecosustainability and biodegradability of the composites. Among several grades of natural fibers, bamboo fibers offer numerous environmental and cost benefits and possess excellent mechanical characteristics. The superior properties of the bamboo fibers have triggered the research interests in the domain of bamboo fiber-reinforced polymer composites. Among the polymers, polyesters are long chain molecules made up of atoms arranged in various ways with other elements to form the basic building blocks of a polymeric chain. Polyester is being increasingly employed in today's industrial products due to its inherent advantages. As a result, based on the potential properties of bamboo fibers as reinforcing materials and polyester resin as matrix material, the biocomposites are synthesized by hand lay-up technique and the specimens cut as per the standard dimensions and subjected to mechanical investigations, vibration, and morphological characterization as per the ASTM test methods. The increase in fiber weight content has enhanced flexural, tensile, and impact characteristics and improved the damping characteristics of the composite specimens. The microstructural evaluations have revealed the uniform distribution of the bamboo fibers in the resin, and the morphological studies of the fractured specimens have revealed that the fracture is majorly due to the matrix cracks rather than the fiber debonding, which is a major attribute ascertaining the strong coherent strengthening mechanism brought about by the inclusion of bamboo fiber in the polyester resin. [ABSTRACT FROM AUTHOR]

In this paper several aspects of profound modifications caused by high energy exposures are presented as possible candidates for the efficient adjusting processing of polymer materials. The class of hybrid composites receives special attention due to the large spectrum of formulations, where the interphase interaction decisively influences the material properties. They represent potential start points for the intimate uniformity of hybrid morphologies. Their radiation processing turns composites onto hybrid morphology with expected features, because the transferred energy is spent for the modification of components and for their compatibility. The essential changes achieved in radiation processed composites explain the new material behavior and durability based on the peculiar restructuring of polymer molecules that occurred in the polymer phase. During high energy irradiation, the interaction between intermediates born in the constitutive phases may convert the primary composites into hybrids, integrating them into large applicability spheres. During the radiation exposure, the resulting hybrids gain a continuous dispersion by means of new chemical bonds. This type of compounds achieves some specific structural modifications in the polymer phase, becoming stable hybrid composites. The functional properties of hybrids definitely influence the material behavior due to the molecular changes based on the structural reasons. The radiolysis of the vulnerable component becomes an appropriate opportunity for the creation of new material with improved stability. The radiation treatment is a proper conversion procedure by which common mixtures may become continuously reorganized. This review presents several examples for the radiation modifications induced by radiation exposure that allow the compatibilization and binding of components as well as the creation of new structures with improved properties. This approach provides the reference patterns for the extension of radiation processing over the well-conducted adjustments of polymer composites, when certain material features are compulsorily required. From this review, several solutions for the adjustment of regular polymer composites into hybrid systems may become conceivable by the extended radiation processing. [ABSTRACT FROM AUTHOR]

With fast-paced technological advancements coupled with increasing demands for virtual health care especially during the pandemic, health systems globally are on the cusp of transforming healthcare through emerging technologies. Such paradigm shift in digital healthcare requires effective integration of information, computing, communication, and connectivity technologies sharing health data through the web. The current technologies deployed in healthcare service delivery lack emotional competencies despite the growing demands for capturing and monitoring patients' affections, feelings and emotions. The importance of the emotive Sensory web has been gaining relevance in healthcare and society to remotely monitor patients’ emotional competencies during the pandemic like COVID-19 to minimize infections. In this respect, this paper discusses the significant benefits, trends, technologies, perceived challenges, and ethical issues of the emotive sensory Web in virtual health care. The study revealed that emerging technologies such as artificial intelligence, Internet of Things, Internet of Medical Things, 5G technology, Industry 5.0, big data, cloud computing are paramount in the development and implementation of sensory emotive Web in virtual health care. However, the standardization and synchronization of communication protocols, as well as devices interoperability issues, threatens the integration of these technologies. While the need for emotive sensory Web in virtual health care continues to increase, there are social, technological, infrastructural, economic barriers, security and ethical issues that hinder its implementation. Therefore, there is a need for developing technological infrastructure that supports the integration of appropriate technologies; crafting regional and international legal and regulatory policy through WHO; and standardization and interoperability of sensory devices. [ABSTRACT FROM AUTHOR]

Polymer systems like epoxies are not generally used in the manufacturing of structures on their own since they possess an ordinary level of mechanical properties. Hence, different reinforcing fibres and nanofillers are incorporated into polymer systems, thereby combining some of the properties of the resin with those of the fibres, thus making the resultant composite superior to even some metals. In this research study, the hybrid fibre fillers are added to epoxy composites with alumina nano-filler reinforcement are fabricated and tested to improve the flexural strength of the hybrid composites for use in various applications like automobiles, aerospace, civil engineering, military, motorsports etc. Effects of Alumina nanoparticles on flexural strength of Glass-Nylon hybrid composite have been studied. The factors, levels of factors and number of test model have been considered for the experiments as well as for the analysis is decided based on Design of Experiment method by Taguchi. The experimental results have shown that hybrid composite with an increase in the percentage of nanofiller, increases the flexural strength. The increase in flexural strength is noticed due to the addition of nanoparticles to epoxy, and the nucleating effect of nanofillers that were dispersed thoroughly within the matrix. [ABSTRACT FROM AUTHOR]

A comparative study was made on air conditioning system performance improvement by effective condenser cooling and preheating the refrigerant. This study was described with the experimental investigation through a test rig fabricated from car air conditioning components. In which slight modifications were made such as compressor has to run by the electric motor with provision to measure power consumption during functioning and condenser fan has to replace with exhaust fan enclosed by the cooling pad in which water is supplied with a controlled flow rate using a water pump. Preheating of refrigerant is done using engine exhaust gas with counterflow heat exchanger setup. Air conditioning test rig was run to achieve the desired cooling effect for two processes. The coefficient of performance (COP) was calculated in both operating conditions for the same cooling effect and comparative study was made. The conclusion revealed that a new cooling method showed higher COP than preheating. By this approach, the percentage increase in heat removal rate up 37% was achieved which results in decreases the compressor running time thus mileage of vehicle can be improved significantly. [ABSTRACT FROM AUTHOR]

The various U-geometry parameters in the U-bending process result in processing difficulties in the control of the spring-back characteristic. In this study, the effects of U-geometry parameters, including channel width, bend angle, material thickness, tool radius, as well as workpiece length, and their design, were investigated using a combination of finite element method (FEM) simulation, and statistical analysis techniques. Based on stress distribution analyses, the FEM simulation results clearly identified the different bending mechanisms and effects of U-geometry parameters on the spring-back characteristic in the U-bending process, with and without pressure pads. The statistical analyses elucidated that the bend angle and channel width have a major influence in cases with and without pressure pads, respectively. The experiments were carried out to validate the FEM simulation results. Additionally, the FEM simulation results were in agreement with the experimental results, in terms of the bending forces and bending angles. [ABSTRACT FROM AUTHOR]

The Z-bending process has rarely been investigated because Z-shaped parts can be fabricated by applying two bending steps through V-bending processes. In recent years, the Z-bending process has been increasingly applied to reduce the number of processing steps and fabrication time. However, the number of studies on this process is still lacking, which means there is still difficulty with die and process designs when attempting to control the spring-back/spring-forward characteristics. In this study, to solve these problems, the offset Z-bending process was examined using the finite element method (FEM) and laboratory experiments. Based on the stress distribution analysis, the bending mechanism was investigated and clearly identified by analyzing changes in the stress distribution; the analysis showed that the theories of V-bending processes could not be used for the offset Z-bending process. This study also suggests that for the offset Z-bending process, in which the punch is moveable and the die is fixed, the amount of spring-back should not be equal to each other. In addition, the effects of the bend angle on the spring-back/spring-forward characteristics were investigated and clearly identified by analyzing the changes in the stress distribution. Based on the laboratory experiments, the FEM simulation results showed good agreement in terms of both the bend angles and bending forces. [ABSTRACT FROM AUTHOR]

The safety and durability of bridges designed from weathering steels are conditioned by the development of a sufficiently protective layer of corrosion products. Air pollution, microclimate around the bridge, time of wetness, structural solution of the bridge, and the position and orientation of the surface within the bridge structure all influence the development of protective layers on the surface of the weathering steel. In this article, attention is focused mainly on the microclimatic effects resulting from the road traffic under the bridge. The influence of chloride deposition on the development of corrosion products is evaluated using experimental in situ testing. Two neighboring bridges made of weathering steel and crossing different types of obstacles were selected for this experiment. Relations and dependences between the measured parameters (deposition rate of chlorides, corrosion rates, thickness of corrosion products and the amount of chlorides in corrosion products) are evaluated and discussed. [ABSTRACT FROM AUTHOR]