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Go to Editorial ManagerIn this work it had been focused on the possibility of replacement of steel spring in suspension system by fiber reinforced polymer composite that is responsible for light weight of spring which leads to reduces the weight of vehicle and improve fuel efficiency. This type of spring used in motor cycles, light weight vehicle. The design will be simulated by ANSYS workbench. Then, E-Glass fiber has been used to fabricate helical compression spring of 40% fiber volume fraction of glass. with polyester resin. The deflection of glass reinforced composite spring is more than steel spring but within permissible limit. weight of composite spring is reduced by 57% than of steel.
In this study, the mechanical properties of an epoxy, unidirectional woven carbon and fiberglass composite were investigated experimentally. ASTM used for preparing the composite specimen. Different ranges of mixing ratios of woven carbon and fiberglass with epoxy are studied. Tensile, impact and bending test are carried out to investigate the mechanical properties for produced new composites. After testing the mechanical properties of the specimens, it is noted that adding of unidirectional woven carbon layers will leads to strengthens the samples. The mechanical properties of woven carbon composite are far superior to those of woven carbon composite with fiberglass.
The purpose of this research is to investigate how the fiber orientation and loading axis of a composite material affect its behavior. Consideration was given to two different fiber-to-matrix ratios in order to improve the mechanical properties. Hand lay-up samples were produced in accordance with ASTM D790 for flexural testing. On UTM, tensile and flexural tests were performed on the sample. The effect of fiber orientation modifies the composites' mechanical properties. As the fiber orientation increased, the tensile strength of the composite would reduce. This carbon/epoxy composite test demonstrates better strength than those conducted at (30, 5, 60, and 90 degrees). For flexural tests, a three-point bend at 30 degrees demonstrates excellent strength. Utilizing the three-point bend method, the flexural strength and flexural modulus have been determined. The tensile strength, young's modulus, elongation percentage, maximum load to break the composite, peak load, and flexural strength of single- and double-layered carbon fibers were compared and examined. As the number of layers increased, the adhesion between layers of epoxy and fiber carbon, and glass fiber weakened, causing a decrease in almost all mechanical properties. The fabricated 2024-T3 and epoxy glass fiber had higher fatigue strength than aramid reinforced and lower density than steel alloy utilized in aircraft manufacture.
Double skin composite (DSC) construction or Steel/concrete/steel sandwich construction (SCSS) is an innovative and relatively new form of composite construction that can be used in submerged tube tunnels, bridges deck, nuclear structures, liquid and gas containment structures, offshore and onshore structures, military shelters, and shear walls in buildings. The system consists of a plain concrete core sandwiched between two steel plates interconnected together by various types of mechanical shear connectors. The DSC construction perceives advantages that the external steel plates act as both formwork and primary reinforcement, and also as impermeable, blast and impact resistant membranes. The major duty of the shear connectors is to withstand longitudinal shear force and beam/slab separation, while in the bi-steel type where shear connectors are friction welded at both their two ends to two parallel steel plates, the longitudinal and transverse shear force, as well as plate buckling are resisted. The present paper highlights the previous prime researches concerning the subjects of SCSS composite construction, specifically on the conducted tests (push-out tests, tensile, direct shear tests, and bending tests) in which the components of partial interaction (uplift and slip forces) are resisted by various types of shear connectors.
In this research, polymer polymethyl methacrylate PMMA composite with nano ceramic Zr and HAp material were used to manufacture one part of the implant system (femoral ball head of hip implant). Three set of hybrid materials were fabricated and tested for this study; the first mixtures which contains 100% (PMMA), the second mixtures which contains (90% (PMMA) + 8% (Zr) + 2% (HAp)), and the third mixtures which contains (80% (PMMA) + 18% (Zr) + 2% (HAp)) were investigated. The mechanical properties for these mixtures increased with the increasing of nano ceramic concentration (Zr and HAp) composite material in the polymer compared to pure polymer PMMA sample. However, an increase in the concentration of Zr from 8% to 18% content cause a considerable decrease of the hardness where a drop of homogeneity in Zr- matrix PMMA contact occurred, V Hardness value are (68 ,80 and 70) Kg.mm for three mixture respectively. The wear test was in agreement with results of the hardness test. The weight loss of the above samples of the wear test were (0.041, 0.035 and 0.037) respectively. According to mechanical properties, the best sample contains (90% (PMMA) + 8% (Zr) + 2% (HAp)). The Scanning electron microscopy resolute showed the particles forming semi-continuous network along grain boundaries polymer for second sample mixtures containing (90% (PMMA) + 8% (Zr) + 2% (HAp)), provides a low atomic packing and high energy. This will make the grain boundaries more reactive and strengthen mechanical performance. The Optical microscopy, Scanning electron microscopy and Xray spectroscopy analysis for In vitro test using SBF shows the growth of HAp layer with an increase in concentration of Ca and P elements formed on the surface of the second sample. This display of good results is a proof of the biocompatibility of the polymer sample.
Recently, considering polymer composite in manufacturing of mechanical parts can be caused a fatigue failure due to the very long time of exposure to cyclic loading and may at environmental temperatures higher than their glass transition temperature; therefore, in this paper, a comprehensive investigation for bending fatigue behavior at room and elevated temperatures equal to 60 °C, 70°C, and 80 °C will be done. Rotating bending test machine was manufactured for this purpose supplied with a connected furnace to perform fatigue tests at elevated temperatures. The obtained results appeared that the increase in applied stress and temperature caused a clear reduction in fatigue life; also the addition of carbon nanotubes enhanced the fatigue life at different temperatures by 183%, 205%, 218%, and 240%, respectively while the addition of short carbon fibers improved fatigue life by 324%, 351%, 387%, and 415%, respectively. As well as, Polyamide 6,6/carbon fiber composite appeared fatigue limit at temperatures equal to 20°C and 60°C and stresses approximately equal to 55 MPa and 38 MPa respectively.
In this paper the ability of fabricating laminate composites by manual layup was discussed. Heating method was used to manufacture the composites; heat was applied to approximately 12 hours with specific heat temperature. There were four types of laminate composites fabricated and studied in this research, containing Aluminum alloy 6061 as the common element in all types, two types of fibers; woven Carbon fiber with two different orientations: ±45°, ±60°, random fiberglass and with two types of resin; epoxy resin and polyester resin. Different types of composites were made to determine the effect of CNC milling machine to the measured surface roughness and for specified parameters. The weight fraction ratio of the fibers is 37%, polymer is 34% and 29% for Aluminum. The parameters selected are spindle speed, feed rate and depth of cut. The L9 Taguchi orthogonal arrays, signal to noise (S/N) ratio and analysis of variance (ANOVA) are selected to determine the effect of these parameters; it was analyzed by MINITAB 17 program. The results showed that the parameter were significant more to the epoxy resin specimens than polyester resin specimens. The optimal milling parameters for good surface finish for Aluminum – Carbon fiber composite are at 3000RPM, 1200mm/min, 1.2mm, and for Aluminum – Fiberglass composite are 5000RPM, 1800 mm/min, 2.0mm.
Orthoses and prostheses were Chosen and laminated based on their high Yield, ultimate stresses, bending stresses, and fatigue limit. Response Surface Methodology (RSM) was utilized to find the best values for two parameters reinforcement perlon fiber and percent of Titanium Nanoparticle coupled with the matrix resin during optimization. The response surface methodology combined the expertise of mathematicians and statisticians to construct and analyze experimental models. Using this method, we identified 13 different lamination samples comprising a wide range of perlon number and Ti nano Wt% in their Perlon layer composition. All lamination materials defined by RSM methods and produced by a vacuum system were subjected to a battery of tests, with fatigue tests performed on the ideal laminating material in contrast to laminations created in the first study (Tensile test, Bending test, and Fatigue tests according to the ASTM D638 and D790 respectively). In comparison to the other 12 laminations tested using Design Expert version 10.0.2, the lamination with ten perlon layers and 0.75 percent Ti nano proved to be the strongest overall in terms of Yield, ultimate, and bending loads. This study used composite materials and titanium nanoparticles to characterize and fabricate ankle foot orthoses. Strength in bending should amount to about 70 MPa, around 85 MPa in tensile tension. Two empirical quadratic equations for the models of peak bending strength and maximum tensile stress with 95% confidence were created using the response surface approach and analysis of variance within the design of experiments software.
The purpose of this research is to manufacture and test adjustable sockets for below-knee amputation. This article studies using the pnuematic–pads for adjustable sockets. The manufacturing of an adjustable socket with pneumatic pads goes through several stages: In the theoretical design of the adjustable socket, the suggested materials were studied for the pneumatic pads, tubes, and pneumatic pump which should be suitable for the suggested application. In the experimental work, using composite materials for manufacturing the socket consisting of perlon and resin to achieve the rigid shape and required flexibility for the prosthetic user with the pneumatic pads. After assembling the adjustable socket parts, the pneumatic pads, the pump and the tubes, the socket were tested for several times on the patient. In the last stage, the pressure between the socket and the residual limb was measured using F-socket, and it was found that the results were: anterior (160kPa), lateral (167kPa), posterior (153kPa) and medial (348kPa). By comparing these results with what was previously studied, the pressure between the socket and the residual limb is within the acceptable range. The design provides good suspension and more adaptability to the change in stump volume. A posative feedback was given by the patient who used the prosthetic patient for several days as a trial to measure its safety and comfortablty.
The mixing technique was applied in this study to enhance the strength performance of the cement. The addition of 3% by weight of hydroxyapatite (HA) nanoparticles were mixed with 97% polymethyl methacrylate (PMMA) acrylic polymer, which has a nano size to serve as the matrix material. The surface roughness and continuous porosity of the bone cement were found to be slightly increased by the incorporation of nanoparticles, which enhanced bone-implant osseointegration and ingrowth. Atomic force microscopy (AFM) analysis revealed that the addition of hydroxyapatite (HAp) nanoparticles resulted in a surface roughness value (Sa) of 16.25 nm, which is similar to that of natural bone. The energy-dispersive X-ray spectroscopy (EDS) mapping results discover precentor material and uniform distribution. The Sample exhibited promising results in the antibacterial test, showing efficacy against bacteria both with and without sterilization, confirming its antibacterial properties. The mechanical tests conducted on the sample, including tensile, compression, bending and Vickers hardness tests, yielded favorable results and indicated that the sample is suitable for its intended application. In the theoretical works the design of the bone, screw, and bone plate was conducted using SolidWorks, followed by an analysis using ANSYS under both axial and bending load conditions. The theoretical analysis revealed that the safety factor was less than 1 when an axial load of 13 N was applied and a bending load of 2 N was applied, indicating that the structure may not be able to withstand these loads safely. Under both ambient and physiologically relevant conditions in the human body, HA and PMMA have demonstrated to be excellent choices for enhancing the clinical performance of bone cement. This, in turn, can lead to increased longevity of implants, decreased patient risk, and lower healthcare costs
This work involved two major parts: the first one is the experimental part which included treatment of scoliosis deformity by manufacturing thoracolumbosacral orthosis, measuring the cobb angle of deformity, measuring the gait cycle data and walk path for both legs and suggesting a composite material to improve the mechanical properties of the orthosis and finally the interface pressure between trunk and orthosis is measured for twelve points covering of the total TLSO surface area by using f-socket devise. The second part of this study is the numerical simulation part during which the stresses are calculated using Ansys software for calculating stresses due to interface pressure loading boundary condition. The result shows no deference in gait cycle phases but the clear difference noted in walking path due to deviate center of mass, maximum pressure recorded left thoracic region with 900KPa due to correct spinal deformity while the minimum pressure recorded at right chest with l40KPa because of it is tissue region and Maximum value of stress was recorded at the left thoracic region with 2.81MPa due to Maximum interface pressure at this point.
Industrial activities significantly affect the environment by releasing many organic pollutants, including industrial dyes, phenols and antibiotics, which produce wastewater. Effective removal of these substances from wastewater has appeared as a noticeable research field owing to its environmental significance. Exorbitant operational expenses and the potential generation of supplementary pollutants load conventional techniques like adsorption, membrane separation, and coagulation. Semiconductor-based photocatalysis has effectively degraded organic contaminants into less toxic or biodegradable compounds. The construction of robust visible-light-sensitive photocatalytic hybrids for environmental decontamination is an inspiring task for researchers. The exceptional photocatalytic performance of silver halides (AgX, where X is I, Cl, and Br) has recently attracted significant consideration as photocatalysts. Moreover, the combination of silver halides with other photo-active semiconductors to create efficient visible-light-driven photocatalyst heterojunctions has significantly promoted the broader application of the photocatalysis process with enhanced efficiency. Ag-silver halides/semiconductors heterojunctions have developed as crucial components in efficient composites for photocatalysis through surface plasmonic actions, helping with visible light absorption. The current study overviews the most recent Ag and silver halide-based composite photocatalysts. Additionally, it provides an essential understanding of their promoted photocatalytic performances and their main applications in organic pollutant degradation. Moreover, the photocatalytic mechanisms and environmental applications of AgI and composites were discussed.
Flexible and rigid pavements are commonly built for airport pavements to support the moving loads of aircraft during the pavement design life. Airport pavements represent a cornerstone of the aviation world. Their condition profoundly impacts safety, operational efficiency, airport capacity, and financial well-being. These meticulously engineered surfaces must withstand the immense stresses generated by aircraft during takeoff, landing, and taxiing. At the planning stage, the pavement structure, materials, aircraft loads, environmental conditions, and pavement damage models should be evaluated. Comparing with road pavement design, airport pavement structural design is unique in terms of the traffic loads supported by pavements with high load magnitude, significant tire pressure, and dynamic traffic conditions. Over time, deterioration stemming from environmental exposure, aircraft loading, and other factors becomes inevitable. This study aims to explore the various factors influencing airport pavement performance, review the existing methodologies for pavement design and maintenance, and propose enhancements to current practices to ensure long-term durability and safety of airport pavements. This study aims to explore the various factors influencing airport pavement performance, review the existing methodologies for pavement design and maintenance, and propose enhancements to current practices to ensure long-term durability and safety of airport pavements.
Solar panels are constantly evolving, with changes occurring in the materials used, panel shapes, and the method used to attach solar cells to the panels. Solar radiation consists of two components: photovoltaic energy, which is used to generate electricity via photovoltaic panels, and thermal energy, which, on the other hand, can reduce the efficiency of photovoltaic panels. Thermal photovoltaic panels are a recent breakthrough in the industry as they use light to generate energy and heat to reheat cryogenic liquid for a variety of purposes. One subtype that is gaining popularity is hybrid photovoltaic thermal panels, which are designed to enhance heat use by adding a heat storage medium, with phase change materials being a noteworthy example. Despite their numerous benefits, these materials have limited heat conductivity, necessitating substantial research efforts to improve this attribute. However, most research focus solely on enhancing conductivity without applying the findings to PV panels in a comprehensive manner. This study fills this gap by reviewing the phase change materials accessible locally, picking Iraqi wax, researching additions, selecting micro- particles of aluminum oxide (Al2O3), investigating the mixing procedure, and calculating the ideal mixing ratio (6% additive to wax). The combination is then placed to a normal solar panel, resulting in a hybrid photovoltaic panel with a complicated phase transition material reinforced with aluminum oxide.