Print ISSN: 1681-6900

Online ISSN: 2412-0758

Main Subjects : Material

Martensitic Stainless Steel Brazing by Using Ag-Cu-Ti as Active Filler Metal Alloys

Salemah A. Muhammed; Fadhel A. Hashim; Ayad K. Hassan

Engineering and Technology Journal, 2023, Volume 41, Issue 6, Pages 1-8
DOI: 10.30684/etj.2023.136810.1325

Brazing fillers for joining applications are essential to advanced material design and fabrication. Several types of brazing fillers have been developed in recent decades to join similar or different engineering materials. Important parts of automotive and aircraft components, including steel, are often joined by brazing. In this study, Similar samples of martensitic stainless steel were welded by the brazing method, using effective silver-based metal alloys. The brazing welding is done in inert gas atmosphere furnaces, by placing the samples in a special container filled with argon gas during the welding period and at a flow rate (10 to 15 minutes) inside a cylindrical furnace. Three types of metal alloys (silver, copper, and titanium) with different weight ratios of Ag, Cu, and Ti were used with a fixed welding time (10 minutes) at an appropriate temperature for each joint. A set of examinations and tests were conducted to find out the microscopic structure of the bonding site and the extent of the binder overlapping with the base material.  Optical microscopy was used to study the microstructure of the weld joint. Optical and scanning electron microscopy (SEM) is used to study the joint microstructure. All joints of samples exhibited continuous bonding between the base metal and the filler metal, good wetting between the surfaces, and it was also noticed that the higher the proportion of titanium, the better the wetting between the surfaces., the greater the percentage of diffusion of the filler elements and the strength of the bonding with the base metal. The use of titanium-containing fillers in brazing is good for bonding in turbine blades of martensitic steel.

Evaluation of PCL Electrospun Scaffolds Concentration on Metformin Hydrochloride Release Ratio

Saja A. Moosa; Akram R. Jabur; Emad S. Al-Hassani; Ahmed M. Al-Shammari

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1671-1682
DOI: 10.30684/etj.2021.131990.1079

The study investigates the effect of polycaprolactone (PCL) concentration on the metformin hydrochloride (MH) release ratio of electrospun nanofiber scaffolds. Blend and emulsion electrospinning are used to produce the scaffolds. The performance of nanofibrous scaffolds was evaluated by morphology (Field Emission Scanning Electron Microscopy, FESEM), chemical (Fourier Transform Infrared Spectroscopy, FTIR), thermal (Differential Scanning Calorimetry, DSC), wettability, porosity, mechanical tests, and in vitro drug release. The average fiber diameter ranged from (189.29-2893.93 nm) according to the FESEM results, and it increased with PCL concentration. The average fiber diameter of the electrospun scaffold, prepared by the blend method (259.64±6.1 nm), is lower than that of the electrospun scaffold produced by the emulsion method (487.45±22.53 nm). Melting points of all drug-loaded scaffolds were identical to those of pure PCL polymer. Compared with blend electrospun nanofibers, emulsion electrospun nanofibers showed a marked increase in hydrophilicity. The tensile strength indicated an improvement in the mechanical properties with a decrease in the average fiber diameter. Moreover, the results show that the release of Metformin hydrochloride decreases with the concentration of polycaprolactone. Total MH release from (5% w/v) PCL-MH fibrous scaffolds for three-week was 71.11 % and 93.91 % from the emulsion and blend methods, respectively. The drug release ratio is lower in emulsion electrospinning than in blend because the drug is encapsulated by polymer and surfactant, which improves control and long-term drug delivery system DDS.

The Impacts of Calcium Ions Substitution in Hydroxyapatite with Neodymium and Zinc on Biological Properties and Osteosarcoma Cells

Suha Q. AL-Shahrabalee; Hussein A. Jaber

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1650-1658
DOI: 10.30684/etj.2022.133915.1217

Hydroxyapatite (HA) is one of the important biomaterials in the medical field, especially in bone treatment, because of its biological properties close to human bone. A simple co-precipitation technique was used to integrate neodymium and zinc into HA by adding neodymium nitrate and zinc nitrate as a source of substituted elements during synthesis through the wet precipitation method with controlled temperature and pH. Finally, substituted HA was sintered at 800°C after completing the biomaterial preparation. The resulting Nd-Zn/HA was globe-like with nanoparticle size. The Ca+Nd+Zn/P ratio was equal to 1.63, which is relatively close to the molar ratio of bone. Also, the ability of Nd-Zn/HA to cause apoptosis in osteosarcoma cells was discovered. The anti-tumor actions are amplified when increasing the concentration of substituted HA. Therefore, Nd-Zn/HA is a potentially effective biomaterial in osteosarcoma treatment. Meanwhile, it has antibacterial and fungicidal properties against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Escherichia coli, and Candida albicans—one of the important properties required in biomaterials to protect the part that is being treated after the biomaterial is implanted inside the body. The inhibition zone of Nd-Zn/HA ranged between (20-31)mm, much higher than gentamicin and nystatin.

Epoxy-Nanoceramic Composites for 5G Antennas

Hasanain B. Altalebi; Alaa A. Atiyah; Saad B.H. Farid

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1795-1802
DOI: 10.30684/etj.2022.134894.1254

Epoxy–nanoceramic composites of BiVO4 (BVO), LaNbO4 (LNO), and Li6Mg7Ti3O16 (LMT) were prepared using the solvent mixing method. The ceramic nano-fillers volume fractions were (5, 8, 10, and 12%). X-ray diffraction (XRD) and Atomic Force Microscopy (AFM) were used to investigate the crystal structure and size distribution of nanoceramics, respectively. The dielectric constant and loss tangent were measured in the frequency range of (4-8) GHz. The measurement technique was the waveguide approach via a Vector Network analyzer (VNA). The effect of the volume fraction of ceramic fillers on the dielectric constant and loss tangent of the composites at 5.28 GHz (5G) was investigated. This work aims to design composite materials for 5G antennas of lower cost while maintaining the properties of 5G antennas. The results show that an optimum volume fraction of the ceramic filler brings the dielectric properties to their best value. However, epoxy composite with a 5% volume fraction of LMT shows good microwave dielectric properties (dielectric constant = 2.17 and loss tangent = 0.011) at 5.28 GHz. In addition, epoxy- LMT composite with an exceptionally low volume fraction of 5% provides a low-cost material for a 5G antenna. Another aspect of the cost reduction is the elimination of the costly and troublesome compaction and high-temperature sintering process. Furthermore, the epoxy composite overcomes the disadvantages of the high brittleness of the sintered all-ceramic products. As a result, epoxy composite with the 5% volume fraction of LMT is a potential candidate for 5G antenna materials.

Characterization of the Efficiency of Photo-Catalytic Ultrafiltation PES Membrane Modified with Tungsten Oxide in the Removal of Tinzaparin Sodium

Reham R. Abdullah; Kadhum M. Shabeeb; Aseel B. Alzubaydi; Alberto Figoli; Alessandra Criscuoli; Enrico Drioli; Qusay Alsalhy

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1633-1641
DOI: 10.30684/etj.2022.134070.1219

One of the polymeric membranes' main limitations is their susceptibility to fouling, lowering the membrane's performance with time. Therefore, incorporating nanomaterials in polymer matrices has attracted great attention in wastewater treatment applications. It's a promising approach for enhancing membrane hydrophilicity and performance.  Herein, ultrafiltration nanocomposite membranes were synthesized by applying the phase inversion method through immobilizing (0.1-0.4 wt.%) tungsten oxide (WO2.89) nanoparticles in a polyether sulfone (PES) matrix. Membrane's anti-fouling performance was evaluated against tinzaparin sodium. The data showed that the pure water flux improved with increasing nanoparticle loading, reaching its optimum value of 54.9 kg/m2 h at 0.4 wt.% WO2.89 nanoparticles compared to the neat membrane's 30.42 kg/m2 h. The results also demonstrated that the rejection efficiency and flux recovery ratio (FRR) against tinzaparin sodium was enhanced, by 44.89% and 12.69%, respectively, for the membranes modified with 0.4wt.% WO2.89 nanoparticles loading compared to the neat PES membrane. The data also showed that after exposing the nanocomposite membranes to UV light irradiation (λ=365 nm) and intensity (1200mW/cm2) for 1h, a further enhancement by 8.34% in FRR as compared to the membranes with the same percentage of nanoparticles loading without irradiation. It is concluded that the photocatalytic activity of WO2.89 nanoparticles in the decomposition of organic molecules on/close to the membrane surface was the impact that caused this improvement in membrane anti-fouling property

Nanocatalyst for the Degradation of Plastic Waste to Produce Paints

Shams N. Almutalabi; Mohammed Alzuhairi; F. A. Hashim

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1757-1764
DOI: 10.30684/etj.2022.132459.1118

Recycling consumed commercial polymers is considered a highly important issue that chemists and engineers must take care of to develop the proper recycling techniques. The main objective of this study is to find a radical solution to the problems of plastic waste by recycling plastic waste (water bottles) and studying the effect of the produced Degraded Polyethylene Terephthalate (DPET) on the properties of paints. DEPT was added in six quantities to the paint mixture (1, 3, 4, 5, 7, and 14 grams). The paints were evaluated using various tests, including scanning electron microscopy (SEM), viscosity, adhesion, brightness, color, ultraviolet reflectance, and accelerated weathering. Testing the paint mixtures showed that the samples were not affected by weather conditions. This indicates the improvement of the paint mixtures by adding quantities of DPET. This study concludes that the catalyst ratios used succeeded in cracking DPET and avoided the need for large quantities of the catalyst. The use of  DPET in various material applications reduces the cost due to the low cost of DPET production. The use of PET in sustainable applications conferred a radical solution to plastic waste problems worldwide. In this work, mixing plastic waste products, after their treatment, in the preparation of paint mixtures successfully contributed to improving the required specifications.

Investigation of Compression and Hardness for UHMWPE Bio-composites as Internal Bone Plate Fixation

Tamara R. Kadhim; Jawad K. Oleiwi; Qahtan A. Hamad

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1783-1794
DOI: 10.30684/etj.2022.135083.1258

Bone plates are essential for bone fracture healing because they modify the biomechanical microenvironment at the fracture site to provide the necessary mechanical fixation for fracture fragments. This paper addresses the use of composite bone plates in healing long-bone fractures such as transverse fractures of the femur. However, stress shielding in the bone due to metal plates can be reduced by designing implants with Bio-composites that involve Ultra high molecular polyethylene reinforced (UHMWPE) with Nano hydroxyapatite (n-HA) and Nano titanium dioxide (n-TiO2) particles at different weight fraction (0,1.5,2.5,3.5and 4. 5%) and 5% of carbon and Kevlar fibers. FRIT spectrum was used to identify the incorporation between the matrix and Nano particles, and the shifting in main peaks confirmed the good cross-linking within the composite structure. The specimens thus prepared were subjected to a compression test, hardness test, and density. The results indicated that UHMWPE+4.5%n-HA+CF hybrid biocomposite has the highest compressive strength and hardness properties. In contrast, UHMWPE+4.5%TiO2+CF has the highest density, which increased with increasing percentages of weight fraction of Nano-particles, where the compression strength 53 MPa, hardness property ranges 65.6 shore D, and density 1.09 (g/cm3). According to the current study's findings, it is possible to create bio-composites as internal fixation device with improved performance by placing different fiber reinforcements.

An Investigation on The Effect of Carbon Nanoparticles on The Properties of Carbon Brushes

Ahmed A. Alasady; M. I. Mohammad; Suleyman Basturk Basturk

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1744-1756
DOI: 10.30684/etj.2022.135387.1270

The demand for carbon brushes with specific properties and improvements in production economics in recent years has led to increased interest in metal-graphite composites. Metal matrix composites are considered excellent materials to obtain properties superior to those of the constituent phases and meet the specific requirements of material application. In the present study, we suggested a new composite material by utilizing nanomaterials to improve the properties of metal-graphite composite material usually used as carbon brushes. This has been achieved by adding different percentages of 0.1-0.5wt % of carbon nanotubes, carbon nanospheres, or both to the metal matrix composite. The samples were prepared by powder metallurgy technique. The XRD results gave a sharp line and indicated a high crystalline structure and little amorphous, which improved the conductivity performance of the composite produced within the structure of this work. The density measurement chart results showed an increase in the amounts of the carbon nano additives leading to a decrease in the density of the sample. The investigation of nano additives on hardness showed that increases in the additive led to reduced hardness. On the other hand, the resistivity values have reduced gradually when there is an increase in the amounts of the carbon nano additives, especially on the CNT, which gives better results than CNS, which we obtained the resistivity value =(0.32 Ωcm), Comparing with commercial-grade containing free of nano additives (1.3Ω cm).

Effect of Adding MgO on Microstructure of Zirconia Toughened Alumina (ZTA) Composite for Medical Applications

Alaa S. Taeh; Farhad M. Othman; Alla A. Abdul-Hameed

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1731-1743
DOI: 10.30684/etj.2022.134694.1245

Zirconia toughened alumina (Biolox delta) is a new-generation ceramic with four times the strength of alumina alone, used in artificial joints. The composite ZTA, consisting of 82 wt. %Al2O3, 17 wt. % ZrO2, 0.5 wt. % Cr2O3, and 0.5 wt. % SrO, was made using the sol-gel process, starting with salts. To investigate the effects of MgO on the ZTA microstructure, two concentrations (0.25 and 0.5 wt. %) of MgO were added to biolox during gelation to study the ZTA microstructure. Powders were sintered in the air for 2 hrs. at 1450 ºC. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray analysis (EDX) were used to characterize sintering powders. ZTA + xMgO structural characteristics differ from pure ZTA's.  According to XRD calculations, grainsize decreased from 41.82 nm to 31.88 and 26.83 nm with increasing MgO concentration, but the specific surface area (SSA) increased from 40.63 to 54.79 m2/gm while crystallization improved. SEM examination shows the composite has a homogeneous dispersion of shaped particles. The EDX test shows the composite's homogeneous element distribution. ZTA+ xMgO powders were more antibacterial than ZTA powders. MgO inhibits bacterial activity and grain formation in ZTA composite during sintering, which makes it a good choice for medical applications, mainly artificial joints.

Investigating the Effect of Different Parameters on Physical Properties of Metakaolin-Based Geopolymers

Ahmed J. Abed AL-Jabar; Hanna A. Al-Kaisy; Sarmad I. Ibrahim

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1702-1711
DOI: 10.30684/etj.2022.132691.1138

Recently, geopolymers have received widespread attention due to their ability to completely replace ordinary cement with better efficiency, lower cost, and less damage to the climatic environment. This paper aimed to prepare MK-based geopolymer cement at ambient temperature with different alkaline activators and processing parameters. XRD, PSA, DTA-TGA, SEM, and other techniques have characterized the prepared samples. ANOVA test was employed to identify the main effect of the processing parameters. Results showed that the incorporation of potassium ions has a negative effect on the physical properties of GP, in which the presence of such ions tends to decrease the density of GP. Furthermore, the apparent porosity and water absorption were increased. For Na and K, Na-activated GP, it was also concluded that the density of GP increases by increasing Si/Al ratios. Despite the Na-based GP processes having a larger density in compared to the K, Na-based ones. The results also suggested a strong effect of the W\MK ratio on physical properties, in which decreasing this ratio is necessary to achieve GP with better properties. The findings also revealed that a one-minute mixing period was sufficient for producing a homogeneous and dense GP paste.

The Effect of Ceo2 Addition on Transformation Temperatures and Wear Resistance of Cu-Al-Ni Shape Memory Alloys

Dina F. Hammadi; Raad S. Ahmed Adnan; Mohammed A. Al-Sarraf

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1712-1722
DOI: 10.30684/etj.2022.132840.1144

SMAs can switch from one crystallographic structure to another in response to temperature or stress stimuli. When SMAs are exposed to mechanical cyclic stress, they can absorb and discharge mechanical energy by experiencing a reversible hysteretic shape change. SMAs are widely used for sensing, actuation, impact absorption, and vibration damping. This work studied the effect of  CeO2 addition on the transformation temperature and wear resistance of Cu-Al-Ni SMAs. WhereCeO2 was added at different percent’s 0.5, 1, and 3 wt% to the base alloy, followed by casting and homogenization at 900oC. Some tests were carried out: Differential scanning calorimeter, Optical Microscope, Scanning Electron microscopy, Energy dispersion spectrometer, X-Ray Diffraction, and Wear and Hardness tests. OM and SEM tests reveal that both phases of martensite β and γ are found. Also, the additions of CeO2 show a visible effect on phase formation and transformation temperatures. It was observed that increasing of CeO2 particles in Cu-based SMAs owing to improve interfacial bonding between matrix and reinforcement and also observed that the variants become thicker with increasing in percent. Additions of different percentages of cerium oxide increase the hardness of Cu-Al-Ni SMAs. Due to the addition of CeO2 particles, the sample's wear rate decreases compared to pure SMAs.

Synthesis ZnO heterostructured nanophotocatalyst simulated solar light irradiation for removal contaminate Carbamazepine in aqueous solution

Eman H. Rdewi; Ahmed M.H. Abdulkadhim Al-Ghaban; Khalid K. Abbas

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 901-910
DOI: 10.30684/etj.2021.131136.1007

In this study, zinc oxide nanoparticles (ZnO) were produced in aqueous media to photodegrade harmful carbamazepine compounds (CBZ) in aqueous solution under simulated solar-light using the sol-gel technique with zinc chloride and NaOH as precursors. X-ray diffraction (XRD), FTIR analysis, Field Emission Scanning Electron Microscopy (FE-SEM), and UV–vis diffuse reflectance spectra (UV-vis DRS) were used to analyze the ZnO NPs powder. According to the XRD results, ZnO nanoparticles showed a hexagonal symmetry shape with 13 nm particle size value. The absorption bands of ZnO nanoparticles were identified using FT-IR spectra peaking. The ZnO nanoparticles produced in this work are spherical, as seen in the SEM picture, with a band gap of about 3.6 eV. The prepared Zinc Oxide nanoheterostructured photocatalyst utilized excellent performance in reducing Carbamazepine compound with an efficiency of 90%. This study took into account pH solution, catalyst loading, kinetic studies, TOC removal, regeneration, and reusability. The synthesized ZnO successfully removed the Carbamazepine medicine at pH=4. With an R-square of 0.99855, the produced photocatalyst fits well into the pseudo second order model. The ZnO heterostructured nanophotocatalyst retained its outstanding performance after numerous cycles of usage. For these observations, the Zinc Oxide heterostructured photocatalyst for Carbamazepine reduction is a promising photocatalyst.

Structural Characterization of (Mg(1-x)pbxO)-NPs by Modified Pechini Method

Israa A. Najem; Fadhil Abd Rasin; Shaker J. Edrees

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 11-20
DOI: 10.30684/etj.v40i6.2147

The structural characterization was discussed in the present paper of the pure MgO nanoparticles and the doped (Mg(1-x)pbxO) nanoparticles specimens, where (0 ≤ x ≤ 0.03). The modified Pechini method was used to prepare all the specimens. From (DTA), the convenient temperature of decomposition from Mg(OH)2 to MgO was above 375°C. The structure investigation (XRD) revealed that all the specimens have identical space groups and index well to cubic structures. The obtained crystallite size by Scherrer''s equation was increased with increasing the fraction of doping except for (Mg0.97Pb0.03O) due to the formation of PbO oxide. The molecular vibration by FTIR demonstrated that all the pure and doped specimens have the same framework. As the incorporation of Pb2+ ions increases, the bands get broader, and the intensities increase in the ranging 800-400 cm-1 due to vibrations of O-Mg and O-Pb bands, respectively.

Preparation of CuO/ZnO Nano-Particles Using Sol-Gel Technique and Studying the Characterization

Doaa A. Yassen; Farhad M. Othman; Alaa A. Abdul Hamead

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 862-868
DOI: 10.30684/etj.v40i6.2104

Copper oxide (CuO) and zinc oxide (ZnO) are two of the most promising oxides under development right now. The sol-gel technique was used to make Nano composite particles NCPs of ZnO-CuO. The copper (II) nitrate rehydrate 0.1M and zinc nitrate hex hydrate 0.1M liquids were mixed in a 1:1 ratio, and the gel was formed at 80 °C, then dried and calcined for various times 500 °C (3, 5, and 7 hours). Particle size analyzer (PZA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and apparent density were used to characterize the CuO/MgO particles. The x-ray diffraction results showed that the phases of the composite particles were pure. FESEM scans, on the other hand, revealed nanoparticles incorporated in the ZnO-CuO matrix with particle sizes ranging from 60.76 to 145.1 nm. The density of the aforesaid samples was 0.1382, 0.1418, and 0.1469 g/cm3 in that order, increasing as the calcined duration increased. This promotes crystal formation, and CuO/MgO has strong catalytic activity for advanced applications.

Properties of Welded Copper Tubes Fabricated Via Friction crush Welding

Abdul Jabbar S. Jomah; Akeel D. Subhi; Fadhil A. Hashim A. Hashim

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 840-847
DOI: 10.30684/etj.v40i6.2292

The welding process is one of the fabrication processes in which tubes can be performed for structural purposes and transport liquids or gases. This study is focused on the manufacturing, characterization, and evaluation of mechanical properties of welded tubes made from oxygen-free copper (C1020) sheets using friction crush welding. The welded tubes were produced using different tool rotation speeds (1500, 1600, and 1700 rpm) and feed rates (130, 140, and 150 mm/min). The flanged edge height of 2.5 mm and 0.5 mm gap between the ends of the copper sheet was used. All examinations on welded tubes were achieved using different instruments such as optical microscopy, SEM, hardness, and tensile testers. The microstructure study showed good weld quality and good material flow between the two ends of the copper sheet in the weld zone. Moreover, the weld zone was not defective. The lowest hardness was identified in the crush zone due to the coarseness of the copper grains. The highest tensile strength of 105 MPa was obtained at the tool rotation speed of 1500 rpm and 130 mm/min feed rate. The results also showed that ductile fracture is the main source of failure.

Electrostatic Deposition of Poly(Methyl Methacrylate)/Titanium Carbide Coatings on Austenitic 316L Stainless Steel Implant

Ghofran Dhafer; Mohanad N. Al-Shroofy; Hanaa A. Al-Kaisy

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 918-925
DOI: 10.30684/etj.2022.131478.1038

316L stainless steel alloys are extensively used in orthopedic applications for the fixations and substitutions of defective bone tissues in the human body because of their excellent combination of mechanical and biological behavior. However, just like other metallic implants, they tend to release some toxic ions that may lead to serious health issues. Therefore, this study attempts to increase the alloy's resistance against corrosion while maintaining its good mechanical properties by applying a modified coating layer of PMMA-based composites titanium carbide as reinforcement material using dry electrostatic spray deposition (ESD) under constant conditions (25 kV, 15-20 cm distance, compressed air of 15 psi, and spraying angle about 45.0o for 3 0sec). The titanium carbide was added with ratios of (5, 10, 15, 20) wt. % respectively. The coatings’ surface morphology and phases were studied using Field Emission Scanning Electron Microscope, Energy-dispersive X-ray spectroscopy, and X-ray diffraction. Also, the biological behavior of the composite coated samples was studied by investigating their corrosion and wetting attributes. The results revealed that homogenous, uniform, crack-free coating layers and high surface wettability were obtained. Indicating the suability of PMMA/TiC for biomedical applications due to the alloy's improved corrosion resistance and biocompatibility.

Study the Growth of Apatite Layer on Biodegradable Glass as Bioactive Scaffolds

Zainab I. Dhary; Alaa A. Atiyah; Saad B. H. Farid

Engineering and Technology Journal, 2022, Volume 40, Issue 6, Pages 892-900
DOI: 10.30684/etj.2021.131678.1048

Bioglass offers a variety of uses for tissue engineering due to its good biocompatibility and chemical composition, similar to a mineral portion of the body. The synthesis of bioglass 13-93 scaffold was achieved by salt leaching technique, and potassium chloride (KCl) was used as porogen with particle sizes of (200-250) μm. Then, sintering to 750 ◦C for around 1 hour was performed. The resultant materials were examined by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). They were immersed in a solution of simulated body fluids (SBF) for 7 and 14 days, respectively. Initially, calcium phosphate was created. After 7 and 14 days, the surface comprised of developed crystalline apatite. The bioactivity of scaffolds that were created and examined. The FTIR, SEM, and XRD experiments were done before and after immersion of the sample in SBF. The results showed that the scaffolds contained open and interconnected pores with porosities ranging between (75-78%). The maximum value of compressive strength of the prepared scaffold was about 5.6MPa. Based on the obtained results, the glass scaffolds can be considered promising for bone defects and replacement applications

Effect of the Waste Rubber Tires Aggregate on Some Properties of Normal Concrete

Abdul R. Kamel; Ahmed H. Ali; Nahedh Mahmood; Mohammed M. Kadhum

Engineering and Technology Journal, 2022, Volume 40, Issue 1, Pages 275-281
DOI: 10.30684/etj.v40i1.2166

Waste rubber tires are considered to have substantial environmental and economic impacts, and they are non-biodegradable.  This study aims to get rid of waste tires as much as possible and study their benefits and effects on concrete using (chips and crumbs) as an aggregate substitution to fine and coarse aggregates together in making concrete (CRC) and at different percentages of (5, 10, 15, 20, and 25) % by volume. This use can reduce the risk and effect of waste tires. The tests reported a reduction in workability, compressive, and flexural values with the increase in the substitution rate of rubber. Still, other properties such as density and thermal conductivity improved. The registered highest decrease was 2013 kg/cm³ to density and 0.56 (W/m.k) to thermal conductivity with replacement of 50% from waste rubber tiers as an aggregate. The workability registered the highest decrease of 35 mm, compressive strength was 18.5 MPa, and flexural was 3.35 MPa. However, the failure of the (CRC) samples test was not as brittle and abrupt as in the control sample (NSC) in the flexural test.

Preparation of Metakaolin Based Geopolymer Foam Using a Combination of Na and K Types of Alkali Activators

mohammed S. Radhi; Ahmed M. Al-Ghaban; Imad A. Disher

Engineering and Technology Journal, 2022, Volume 40, Issue 1, Pages 282-289
DOI: 10.30684/etj.v40i1.2188

In this research, the ordinary Portland cement (OPC) was mixed with metakaolin, activator, hydrogen peroxide, and olive oil to synthesize hybrid geopolymer foam. The obtained results indicated internal heat release throughout OPC hydration in the combination. OPC was employed as a calcium source in geopolymers (Geopolymer-Portland cement (HGPF)) to explore the curing process of geopolymers at ambient temperature. The functionality of geopolymer components and (HGPF) mixture, the elemental composition, and proportion analyses have been compared. A principal aim of this research focuses on developing geopolymer foam and conducting many tests such as physical tests related to the surface area and pores size and compression of the foam to investigate the capacity of applying this foam in different applications that require good strength. Furthermore, microstructure tests using SEM and XRD techniques have been conducted to examine surface structure components. Overall, the findings presented in this research show that the materials selected to develop the geopolymer foam were compatible with each other giving high porosity with acceptable compression via optimizing the processing parameters by RSM.

Recycling of Wood – Plastic Composite Prepared from Poly (Ethylene Terephthalate) and Wood Sawdust

Halla M. Shehap; Mohammed A. ALzuhairi; Sarmad I. Ibrahim; Saif S. Hussien

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1654-1662
DOI: 10.30684/etj.v39i11.2203

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.

Wild Clary Plant Extract as Corrosion Inhibitor for Carbon Steel in Seawater Medium

Zainab S. Aziz; Rana A. Majed; Majid H. Abd

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1646-1653
DOI: 10.30684/etj.v39i11.2151

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.

Investigation of the Effect of Microcapsule Additive on Mechanical and Physical Properties of Concrete

Reem T. Salmana; Alaa A. Abdul-Hamead; Farhad M. Othman

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1639-1645
DOI: 10.30684/etj.v39i11.2091

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.

Investigation of Some Properties for Laminated Composite Used for Prosthetic Socket

Shereen A. Abdulrahman; Qahtan A. Hamad; Jawad K. Oleiwi

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1625-1631
DOI: 10.30684/etj.v39i11.2050

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.

Improve the Corrosion Resistance of the Copper-Zinc Alloy by the Epoxy-WO3 Nanocomposite Coating

Ban D. Abbass; Kadhum M. Shabeeb; Ayad K. Hassan

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1669-1673
DOI: 10.30684/etj.v39i11.2225

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.

Electrophoretic Deposition Used to Prepare and Analyze the Microstructure of Chitosan/Hydroxyapatite Nano-Composites

Israa Z. Ahmed; Hussein A. Jaber; Shaymaa M. Salih

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1693-1704
DOI: 10.30684/etj.v39i11.2181

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.

Preparation and Characterization of Polymer Blend and Nano Composite Materials Based on PMMA Used for Bone Tissue Regeneration

Sally A. Kadhum Alsaedi; Sihama I. Salih; Fadhil A. Hashim

Engineering and Technology Journal, 2020, Volume 38, Issue 4A, Pages 501-509
DOI: 10.30684/etj.v38i4A.383

As the elderly population increases, the need for bone loss treatments is increasing. Vital substances used in such treatments are required to continue for a longer period and work more effectively. The particularly important biological material is poly methyl methacrylate (PMMA) bone cement, which is widely used in damaged bone replacement surgery. So, this study focused on the role of added some nanoparticles consist of zirconia (ZrO2), and magnesia (MgO) on the binary polymeric blend (Acrylic bone cement: 15% PMMA) for a bone scaffold. Where, ZrO2 and MgO nanoparticle was added with selected weight percentages (0, 0.5, 1, 1.5 and 2 wt.%), which were added to the polymer blend matrix. Some mechanical properties were studied including the tensile strength and young modulus for all the prepared samples. The chemical bonding of nanoparticles and synthetic binary polymeric blend composites was evaluated by Fourier Transform Infrared (FTIR) spectroscopy. Tensile strength and young modulus of binary polymeric blend reinforced with 1.5 wt.% ZrO2, and 1 wt.% MgO, significantly increased. The surface morphology of the fracture surface of tensile specimens was examined by Scanning electron microscope (SEM). The SEM images confirmed that the homogenous distribution of nanoparticles (ZrO2, and MgO) within the polymeric blend matrix.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

Abeer F. Al-Attar; Saad B. H. Farid; Fadhil A. Hashim

Engineering and Technology Journal, 2020, Volume 38, Issue 4A, Pages 491-500
DOI: 10.30684/etj.v38i4A.351

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 ( and it was 0.214( of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.