Engineering and Technology Journal

Polyester has been used as a prosthetic socket base. It is well documented that the raw material of the socket base should have exhibited good mechanical properties. Prosthetic socket is a device that connects an artificial limb with the amputee part. In this work, seven laminated composites were prepared using vacuum technique from polyester resin and reinforced with Jute, Carbon, Glass, and Perlon fibers. The objective of this study is to manufacture prosthetic sockets from different laminated composite materials (fibers reinforced polymer) to make high-strength and durable prosthetic socket design. The results showed that the best laminated composite specimens have three jute fiber layers with four carbon layers whose compression strength and hardness reach (67) MPa and (86) Shore-D, respectively. Also, the water absorption of the composite specimen of jute with carbon fibers is higher than that of the composite specimen of jute with glass fiber.

The goal of this research is to study the microstructural analysis and mechanical properties of an aluminum matrix reinforced with different amounts of nano Fe3O4 at (2, 4, 6, 8, and 10wt. %). Al/ Fe3O4 nanocomposites specimens were prepared using the powder metallurgy route. Many examinations, including Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Diffraction (XRD) analysis, were performed on the specimens in this study to determine the microstructure and phases of the nanocomposites. Mechanical tests, such as compressive, microhardness, and wear tests, were also performed to assess the mechanical properties of the nanocomposites. The results of this study show that Fe3O4 nanoparticles have been homogeneously dispersed in the Al matrix by FESEM and XRD examination. While the mechanical tests show improving the compressive strength at 6 wt.% by 5.36%, the highest microhardness was at 10% by 101.6% compared with the pure Al, and improving the wear rate.

Cracks are a fundamental problem in concrete, so this research investigates an experimental study of the effect of adding SiO2 on the self-healing behaviour of concrete. The study is done by studying the physical properties, microstructure, and mechanical properties of concrete. Microcapsules were prepared to contain (cement and nano SiO₂) in a (palettization (fluidize bed coating) method) with (5,10, and 15) % of cement weight. The ratio of the prepared concrete mixture was (1: 2: 4) and the ratio of water to cement (W / C) 0.45 by the weight of cement was also added as 0.6% Superplasticizer to all concrete mixtures. SiO2 MC is added with (2.5) % of the cement weight in the concrete mixture. In this study, porosity, density, and water absorption tests were performed to study the physical properties, compressive and bending strength to study mechanical properties. So, referring to the results, (SiO₂ MC) was used as an effective effect in the self-healing cracking mechanism, and in improving the bending strength and compressive strength. Also, 10 % wt. was recorded as the best addition because it has a positive effect on properties to be applied in construction.

Aqueous extract of wild clary has been used in place of a corrosion inhibitor in the corrosion control of carbon steel. The major components of this extract are Ethan amine, Amino-octadic, and 4H-Pyran-4-one. It has an excellent inhibition efficiency (IE) of 83.078% at a concentration of 20 (mL/L) and a temperature of 298 (K). The extract was characterized by FTIR and GC MS, where the antibacterial was tested and the protective film was analyzed on the samples using FTIR spectra. The protective film formed on the metal surface is confirmed using an electrochemical study by Potentiostat, which revealed that this extract was a mixed-type inhibitor.

Plastic waste has become one of the humanities and the ecosystem balance serious environmental Challenges. Furthermore, it is the primary source of plastic pollution because it is inexpensive, widely available, and frequently discarded. Using various waste materials and side fractions as part of wood-plastic composites is one way to promote the circular economy (WPC). Several environmental benefits can be realized by using recycled plastic, including extending the usable life of plastic, reducing waste, contributing to the development of trash recycling, and preventing resource depletion. One of the most efficient recycling processes is glycolysis; the (PET) is depolymerized by ethylene glycol in continuous stirring reactors at temperatures between 200 and 220◦C using glycol as solvent. This work concentrates on the experimental investigation of composite materials from DE polymerization PET, Unsaturated polyester, and VV/55 as a matrix and wood sawdust as reinforcement. The composite samples were checked by the Hardness test, water test, and density test. According to the experimental results, the optimum value is at (2%) wood percentage, giving high hardness value, low density, and low water absorption.

Graphene is one of the most important forms of carbon. Due to its exceptional physical, chemical, and mechanical properties, it’s used in different fields such as electronic, energy storage, and medical applications. Therefore, the production of graphene in large quantities, at a low cost, and high quality, has become critical. Using graphite powder, a few layers of graphene sheets were prepared via a series of mechanical exfoliation methods. the dry ball milling process by the planetary mill was used. Thereafter, the milling was followed by shear force and then supported by ultra-sonication to reach the lowest level of the graphene layers. Morphological properties were examined using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). Also, structural characterizations were investigated using Raman spectra and X-ray diffraction measurements (XRD) and (FTIR). Findings presented in this research highlighted that the synthesis method followed was found to have several advantages, including low cost and the ease of producing a few layers of graphene nanosheets. Subsequently, the promising efficiency of the used methodology is important.

Metal corrosion is one of the most critical challenges in industrial processes. In this research, nanocomposite coating was synthesized by blending tungsten trioxide (WO₃) nanoparticles with Epoxy resin and applied on brass samples to evaluate the performance of corrosion protection under stressed environments. A dip-coating method was adopted to coat the brass sample's surface. Coated and uncoated brass samples have been subjected to corrosion tests to study the corrosion behavior when exposed to corrosive media. Obtained results indicated that the brass coated samples with mixed epoxy\tungsten trioxide (WO₃) exhibited reasonable corrosion resistance because of the ceramic protective barrier on the surface of the metal. Therefore, the proposed methodology could be considered as a promising surface coating that promotes corrosion resistance under stressed industrial conditions.

NiTi alloys are widely used in biomedical applications for their unique properties particularly the shape memory effect, superelasticity, and biocompatibility. In this research, NiTi/PVA composite nanofibers are fabricated by electrospinning technique, using a novel method of producing NiTi ultrafine particles by immersing amorphous NiTi alloy in dilute aqua regia solution. The NiTi particles are successfully embedded in the PVA matrix. The produced NiTi particles are analyzed by X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS), and Particle size analyzer. The XRD pattern of ultrafine NiTi particles shows much better phases as compared to the XRD pattern of the amorphous NiTi alloy sample. The morphology of the produced NiTi/PVA composite nanofibers are characterized by Field emission scanning microscope (FESEM), and Energy dispersive spectrometry (EDS). The test results show regular continuous smooth bead-free nanofibers.

Kevlar is widely used in ballistic applications to protect against hand pistols, due to its high strength, lightweight, and high impact resistance. Compared to other fabrics, Kevlar is considered a typical material due to its strength properties for bullet-proof vests. This project aims to develop a hybrid composite and investigate its behavior under ballistic impact both experimentally and theoretically. Ceramic/woven fabric reinforced epoxy/polycarbonate multilayered armors were developed. The initial layer of defense against the bullet is silicon carbide (SiC). The intermediate composite is made up of aramid fabric (Kevlar) reinforced epoxy (KEV/EPX). The rear layer was made of polycarbonate (PC). A 9 mm FMJ bullet was fired in 310 m/s, towards samples of 900 cm². To simulate  the ballistic test, Ansys Workbench Explicit Dynamics and Ansys AUTODYN 3D were used. An integrated methodological approach of experimentation and simulation was followed to assess the behavior of samples. Obtained results showed that SiC+ KEV/EPX+ polycarbonate was able to stop the 9mm FMJ bullet and indicated that armor layers perforated without penetration. Back Face Signature BFS was also measured, which is within the allowed limit. The ceramic layer absorbs the largest percentage of the overall energy absorbed, compared to fiber-reinforced epoxy and polycarbonate, which reach 77.8% of the entire energy.

This paper presents the electrical behavior of the top contact/ bottom gate of an organic field-effect transistor (OFET) utilizing Pentacene as a semiconductor layer with two distinctive gate dielectric materials Polyvinylpyrrolidone (PVP) and Zirconium oxide (ZrO₂) were chosen. The influence of the monolayer and bilayer gates insulator on OFET performance was investigated. MATLAB software was used to simulate and determine the electrical characteristics of a device. The output and transfer characteristics were studied for ZrO₂, PVP and ZrO₂/PVP as an organic gate insulator layer. Both characteristics show a high drain current at the gate dielectric ZrO₂/PVP equal to -0.0031A and -0.0015A for output and transfer characteristics respectively, this can be attributed to an increase in the dielectric capacitance. Trans conductance characteristics also studied the gate dielectric materials and show the ZrO₂/PVP gate dielectric having a higher value from the monolayer, indicating the effect of dielectric capacitance.

This research studies the coating layer properties from chitosan and nano –hydroxyapatite made by pulsed electrophoretic deposition (PEPD) for biomedical applications. The 316L SS alloys were coated with hydroxyapatite in different solutions in 100 mL of suspension at a 30 V continuous voltage. To characterize the deposited coatings, X-ray diffraction spectroscopy (XRD), Fourier transform infrared (FTIR), Contact Angle, scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX),Yield deposition and Optical microscopy structural (OM) was used for coating layer, in addition to being calculated Zeta potential for suspensions. The aim of this study is to show that using the Pulsed EPD method at room temperature, a simple and low-cost solution for in situ synthesis of Nano -HAp within a chitosan matrix for biomedical applications can be demonstrated.

In this work, unsaturated polyester, resin, matrix reinforced, with fiberglass mat chopped were developed using TiO₂ and SiO₂ Nanoparticles as filler materials. The individual and combined effects of nanoparticles on the nanocomposite and material properties were examined. An improvement in Young’s modulus (39,3%) using combined weight of TiO₂+ SiO₂ was observed to be 3%. Examined nanoparticles have shown normal distribution in grain size indicated to be within standard limit, therefore boosting nanocomposite material to have excellent hardness, roughness, impact, and flexural resistance. DSC was characterized by transitions in this material. SEM and EDS techniques were used to confirm the formation of TiO₂ and SiO₂. The nanocomposites can be used in light-shielding, applications as well as in the industrial sectors.

In the perspective of environmental advance, significant attentiveness is being displayed in the usage of natural fibers like reinforcement in polymer composites. This paper focuses on building a prosthetic socket arranged from natural fiber-reinforced composite as an effort to substitute material currently accessible in the manufacturing of the socket. The vacuum bagging procedure was adopted to yield a below-knee socket. The laminates encompass woven flax, sisal, cotton, carbon, person, and glass fabric. The impact of diverse fiber layering sequences on some of the physical and mechanical characteristics was assessed. Laminated specimens were characterized by tests such as (hardness, surface roughness, density, water absorption). The results of this study showed that consuming altered forms of reinforcing materials had an abundant influence on the properties of prepared composite and the values of (hardness, surface roughness, and density) properties improved with increasing of the volume fraction of materials and the best composite specimens were three layers of flax with two layers of carbon fiber, were the hardness property ranges 86 MPa and density of (1.276 gm. /cm3) due to their exceptional mechanical properties. The results of the present study advocate that the arrangement of natural and synthetic reinforcements allows the preparation of bio-composites with enhanced performance.

This works aims to investigate the influence of three different categories of silica, namely, precipitated silica, fumed silica and nanosilica prepared via sol-gel process, for hydrophobic application in this work. Nanosilica was characterised using scanning electron microscopy, Fourier transform infrared spectroscopy, particle size and zeta potential. Diluted silicone rubber (room-temperature vulcanising silicone) was also used as a matrix for these particles as (3/1) weight%; silicone rubber/silica. Cold spraying technique was applied to coat glass substrates. Fourier transform infrared analysis was applied to investigate the coating. SEM observation and particle size analysis established that the nanosize of silica is used with narrow-size distribution. Zeta potential analysis demonstrated the stability of nanoparticles at recorded average values of −41 to −50 mV. Wettability results showed that all types of silica incorporated into the silicone rubber present a hydrophobic surface. The maximum recorded value of contact angle was 146° for sol-gel-prepared silica/silicone rubber. The out findings indicated that these compounds are acceptable candidates for hydrophobic glass applications.