Al-Nahrain Journal for Engineering Sciences <p><strong>Al-Nahrain Journal for Engineering Sciences</strong> is an&nbsp;open access academic specialized journal that evaluates and publish scientific papers in all engineering study fields submitted by researchers. It is a <strong>quarterly publication</strong> in English, issued in <strong>Baghdad</strong> under the responsibility of College of Engineering - Al-Nahrain University with the registration number<strong><em> ISSN</em> 2521-9154</strong> and <strong><em>eISSN</em> 2521-9162</strong>.</p> <p>&nbsp;</p> <p>&nbsp;</p> <p>&nbsp;</p> Under the responsibility of College of Engineering, Al-Nahrain University, Baghdad, Iraq en-US Al-Nahrain Journal for Engineering Sciences 2521-9154 <p><strong><span style="text-decoration: underline;">Author(s) Rights</span></strong></p> <ol> <li class="show">Each author retains the right to use the work for non-commercial purposes as well as for further research and spoken presentations.</li> <li class="show">Each author retains the right to use the illustrations and research data in his/her future work.</li> <li class="show">Only one offprint is provided free for each author. The authors can order offprints at the proof stage at certain rates depending on the number of additional copies required and the year of publication.</li> </ol> <p>&nbsp;</p> <p><strong><span style="text-decoration: underline;">Publisher Rights</span></strong></p> <p>The publisher of the journal has all rights for publication in the paper, electronic and facsimile formats and for electronic capture, reproduction and licensing in all formats now and in perpetuity in the original and all derivative works.</p> First Pages <p>Editorial Board</p> Editorial Board ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 I III Study the Effect of Using Microwave Energy in Chemical Processes for Dyeing and Printing Pretreatments of Cotton Fabrics <p>The research focuses on studying the effect of microwave energy as an alternative heating method on dyeing and printing pretreatments of cotton fabrics. In this research, a microwave oven was used to heat the solutions which used in de-sizing, scouring, bleaching and mercerizing processes at different energy levels. The results showed the importance of this heating method in improving desizing efficiency where the best result was obtained at 180 W and 24 min and this method was beneficial in saving energy and time. The best result in scouring was obtained at 720 watts and 24 minutes, whereas at 720 watts and 20 minutes was the best result in bleaching. We can save energy, time and chemicals compared with the conventional method. The mercerizing by microwave increased the absorption of dye solutions for the samples compared with the traditional method, where the color strength increased by increasing the treatment time and the level of energy in the microwave and the best result was obtained at 900 watts and 90 seconds.</p> Lina Mohammad Almirdash Ziad Saffour ##submission.copyrightStatement## 2019-07-20 2019-07-20 22 2 73 80 10.29194/NJES.22020073 The Usage of Time Reverse Technology to Improve The BER Performance and Transmission Rate of IR-UWB System <p>Ultra-Wideband (UWB) technology has so many striking characteristics which includes low sensitivity to fading, superior performance, low interference, easy to penetrate in walls as well as in floor. The main motive of this work is to analyze the capability of UWB technology as various aspects and improve its performance, since the main drawback of this system is that the power spectral density of the transmitted signal is rather limited. The MIMO technology may provide a solution by increasing the received SNR for the same transmission power, but the problem in this case is the spatial correlation resulted. To solve the problem two technologies are integrated along with the UWB using Time Reverse (TR) by TR-MIMO and TR-SIMO. Among these integrations, the robust performance of the UWB is analyzed by comparing the transmission rates for a given outage probability. In the last step, the (SIMO/MIMO)-UWB and TR-(SIMO/MIMO)-UWB were compared in terms of BER values to create the way of applying the UWB in so many applications.</p> Mohammad Alkhaddour Mazen Youssef ##submission.copyrightStatement## 2019-07-20 2019-07-20 22 2 81 87 10.29194/NJES.22020081 Inducing Frictional Force to Enhance the Transient Response in Beams <p>This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity.</p> <p>A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness. </p> Hamed Khanger Mina Waleed K. Al-Ashtrai ##submission.copyrightStatement## 2019-07-20 2019-07-20 22 2 88 93 10.29194/NJES.22020088 Evaluation of Moisture Susceptibility for Modified Open Graded Friction Course Mixes Used Styrene Butadiene Styrene <p>Open-graded-fraction-course (OGFC), is a hot asphalt mixture usually utilized as a private purpose wearing course, because of open graded asphalt mixture and aggregates skeleton (stone-on-stone) contact, it contain a relatively high air voids’ percentage, after compaction which are permeable to water. In this research one type of gradation was used (12.5 mm) NMAS, to preparing the OGFC asphalt mixtures, penetration grade 40/50, crushed aggregate, asphalt content prepared with 4 % and up to 6 % by weight of mixture with 0.5 % increments. Optimum asphalt content (OAC) was selected based on these criteria, air voids content, asphalt draindown, permeability, and abrasion resistance (aged and un-aged) condition. The mix performance had been investigated by indirect tensile strength and moisture susceptibility (sensitivity) measured according to the (AASHTO T283-14). Results illustrate that the increasing of asphalt binder content leads to a decrease of the air voids content, abrasion loss and permeability values, while draindown increase, conversely, the indirect tensile strength (ITS) had been significantly increased for both conditions and this is a gaod suggestion to resistance alongside moisture susceptibility. It can be decided that the increasing of asphalt&nbsp; binder percent in OGFC asphalt mixture, leads to an increase in the thickness of binder coating around the aggregates. On the other hand, the influence of modifier that prepared with 4% styrene-butadiene-styrene (SBS) on OGFC asphalt mixture tends to improve the mix properties and exhibit higher (TSR) as compared with original asphalt by (31, 27.7 and 24.4) % at asphalt percent (4.8, 5.3 and 5.8) %, respectively. The SBS improved the adhesion between aggregate and asphalt which leads to reduce stripping of HMA, horizontal deformation, and increased the tensile stiffness modulus value.</p> Miran Bahyam Ahmed Alaa Hussein Abed Yasir Mawla Hammood Al-Badran ##submission.copyrightStatement## 2019-07-20 2019-07-20 22 2 94 101 10.29194/NJES.22020094 The Porosity Effect of Stainless Steel Balls on Forced Convection Pipe Flow <p>An experimental study has been carried out to investigate the effects of stainless-steel balls on forced convection flow in pipe under uniform heat flux. Water is used as the working fluid and stainless-steel balls as a porous media. The Reynolds number range from (5000 to 9000) based on the diameter of the pipe. The experiments were conducted on three various numbers of stainless-steel balls (N) with various diameters (d<sub>p</sub>), which give various porosity (0.33, 0.38 and 0.41). These are (N= 2400, d<sub>p</sub>=1mm), (N=1600, d<sub>p</sub>=3mm) and (N= 750, d<sub>p</sub>=5mm). Results show that, heat transfer coefficient increases with the decrease in the porosity due to the reduction in the space between balls. This led to an increase in turbulence and produced eddies. Furthermore, enhancement in heat transfer coefficient reached its maximum value of (45%) for ball diameter with (d<sub>p</sub>=1mm) and water flow rate (9 L/min). New Correlation equations for the average heat transfer coefficient were obtained for three different diameters of balls (1, 3 and 5 mm).</p> Ayser Munner Flayh Sajida Lafta Ghashim ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 102 108 10.29194/NJES.22020102 Influence of Stirring Speed on Mechanical Properties for Cast Nano-Particulate AA7075-Al2O3 Composites <p>Aluminum metal matrix composites are widely employed for improving the mechanical properties. Various fabrication routes like liquid state, solid state and liquid-solid state are currently available for producing these materials. The objective of the present work is the fabrication of nano particulate composites AA7075-Al2O3 with different amount of nano particles (20-30 nm) reinforced material Al2O3 (2, 4 and 6 wt%) using stir casting technique at three stirring speeds (300, 850 and 1500 rpm). Tensile tests of these composites were carried-out to obtain the mechanical properties (ultimate strength and ductility). Vickers hardness tests were also performed to obtain the hardness number (VHN) of these materials. All tests were performed at room temperature. The microstructures of the best mechanical properties’ composites were examined for the three stirring speeds. It was revealed that the ultimate strength (Ϭu) and Vickers hardness (VHN) for the composite containing 6 wt% Al2O3 fabricated at 850 rpm show the best properties compared to the other composites fabricated at 300 and 1500 rpm and the matrix. The Ϭu and VHN were increased by about (36.6 %) and (24.5 %) respectively. Ductility of the strongest composite (6 wt% Al2O3 at 850 rpm speed), however, was the least when compared to other composites and the matrix. With increasing the amount of Al2O3, Ϭu and VHN, an increasing trend was noticed while the ductility shows a reduction trend. The maximum reduction in ductility occurred for the composite containing 6 wt% Al2O3 obtained at 850 rpm. The ductility of the developed composite was reduced by (23 %). The optical microstructures of unreinforced, as-cast Aluminum alloy AA7075 and 6 wt% Al2O3 composites for all stirring speeds show dendrite microstructure resulting from the casting process, but the composite at the stirring speed of 850 rpm shows a more refined microstructure.</p> H. J. M. Alalkawi Asifa Mahdi Mohammed Raad Hameed Majid ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 109 116 10.29194/NJES.22020109 Effect of Different Friction Stir Spot Welding Techniques on the Mechanical Properties and Microstructure of Aluminum AA2024-T3 <p>This paper presents a comparison of using different techniques for stir spot welding of Aluminum 2024-T3, which are refill friction stir spot welding (RFSSW), edited (RFSSW-pin) and conventional friction stir spot welding (FSSW), depending on the obtained tensile shear strength property. Specimens were prepared from AA2024-T3 sheet for chemical analysis and mechanical tests. Workpieces were stir spot welded utilizing the above mentioned techniques at four rotational speeds (2000, 2500, 3000 and 4000 rpm) using tool pin diameters (5 and 7 mm) for conducting the tensile shear tests. The microhardness along the cross section of the welded specimens was conducted at the best conditions as well as the microstructure examination. The comparison results revealed that at the rotational speeds (2000 and 4000 rpm) in both cases of tool pin (5 and 7 mm), the ultimate tensile shear force was slightly higher than that for other speeds. However, the ultimate tensile shear force was found higher at 3000 rpm speed with a tool pin 7 mm. The microhardness results manifested a W-shape at the best conditions. Finally, the microstructure examination depicted the morphology of the main zones of the weld joint.</p> Akeel Z. Mahdi Samir A. Amin Sadeq H. Bakhy ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 117 123 10.29194/NJES.22020117 Effect of Alumina (Al2O3) Particles on The Mechanical Properties of Magnesium (Mg) <p>In the present study, magnesium-based composites reinforced with different volume fractions (3, 5, 10, and 15) vol.% of micro sized Al<sub>2</sub>O<sub>3</sub> particulates were fabricated by powder metallurgy technique which involves mixed, compacted and sintered. Powders were mixed by ball milling (without balls) for 6 hours at rotation speed 60 rpm. Then powder was compacted at 550 MPa and sintered at 530˚C for 2 hours. Microstructures of sintered composites have been investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) energy dispersive.&nbsp; SEM image of sinter samples exhibit good bonding between the magnesium matrix and the alumina. The microhardness and wear resistance of micro composites has been improved significantly compared to that of pure magnesium. Highest value of microhardness is 97 HV at the volume fraction of 10 vol.% Al<sub>2</sub>O<sub>3</sub>.</p> Hayder Muneam Abed Zaid Abdul Rahman N. Abed Hala Salman Hasan ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 124 130 10.29194/NJES.22020124 An Investigation of the Shearing Forces Using Blanked Carbon Steel Sheets <p>An important challenge confronted when using blanking to machine sheet metal is the treatment of the shearing force in demand for great strength and heavy stock. One of the methods used to decrease the force wanted is the increase of a punch shear angle. In this work, experiments were conducted to study the effect of shear angle for blank has a diameter (50 mm) on shear force of a low carbon steel sheet (AISI 1008). Low carbon steel is a very common material used in fabrication of sheet metal components, with thickness of (0.5 mm). Tools used in the blanking tests were one traditional flat end punch and four different bevel sheared rooftop punches, which rooftop punches were compared to. and it (0°, 5°, 10°, 15°, 20°) a punches diameter (49.95 mm) by clearance (0.025mm) for each side , with a blanking speed (500mm/min). A special blanking die set is designed and manufactured and was a blank cut by a hydraulic press whose capacity (20 ton). The results showed that the blanking forces of (AISI 1008) low carbon steel metal could be decreased radically with best bevel punch geometry. Using (10°) shear angle at the punch end, the cutting forces decreased up to (90%) compared to the ones of the traditional flat end tool</p> Ahmad Saad Jasim Ali Abbar Khleif ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 131 135 10.29194/NJES.22020131 An An Analysis of Strain Rate Distribution Using Streamline Model and A Quick Stop Device in Metal Cutting <p>In this paper, a quick stop device technique and the streamline model were employed to study the chip formation in metal cutting. The behavior of chip deformation at the primary shear zone was described by this model. Orthogonal test of turning process over a workpiece of the 6061-T6 aluminum alloy at different cutting speeds was carried out. The results of the equivalent strain rate and cumulative plastic strain were used to describe the complexity of chip formation. Finite element analysis by ABAQUS/explicit package was also employed to verify the streamline model. Some behavior of formation and strain rate distribution differs from the experimental results, but the overall trend and maximum results are approximately close. In addition, the quick stop device technique is described in detail. Which could be used in other kinds of studies, such as the metallurgical observation.</p> Osama Ali Kadhim Fathi A. Alshamma ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 136 142 10.29194/NJES.22020136 Development of High Performance (Mechanical and Wear Properties) of AA 6061-Hybrid Nano Composites Via Liquid Metallurgy Route <p>This research is devoted to study the influence of different weight percent concerning to the additions of Ti and Cu on mechanical and tribological properties of AA6061. The composite materials consist of different weight percentage of Ti (0.2, 0.4, and 0.6) wt% and constant weight percentage of Cu (0.2) wt% which were fabricated by liquid metallurgy route technique. Microstructural characterization and phases have been examined by using SEM (scanning electron microscopic).SEM examination showed uniform distribution of nano Ti and Cu in AA6061. The consequences of mechanical tests demonstrated clear enhancement in mechanical properties, such as ultimate tensile strength, yield strength, young modulus, ductility% and hardness at additive percentage of 0.4% Ti+0.2%Cu nano particles incorporated into molten AA6061. Percentage of enhancement ultimate tensile strength is about 73.3%, yield strength about 82.7%, young modulus is about 21.2%, the&nbsp; Vickers hardness about 42.6% and the decreasing in ductility was about 25.2% compared with the metal matrix (AA6061). The wear rate test was performed by using pin on disc rig for both hybrid nano composite and base metal (AA6061) under various loads (10,15and 20) N with sliding speed (1.282) m/sec at a (10) min’s time. The results showed a decrease in wear rate at 0.4%Ti+0.2%Cu compared with the base metal (AA6061). Improvement percentage of wear rate is about 105% at 20 N load.</p> Hussain J. M. Al-Alkawi Abduljabbar Owaid Hanfesh Saja Mohammed Noori Mohammed Rauof ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 143 150 10.29194/NJES.22020143 Guidelines for Authors and Publication Requirements <p>Guidelines for Authors and Publication Requirements</p> NJES Editor ##submission.copyrightStatement## 2019-07-21 2019-07-21 22 2 151 164