Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Mechanical properties

Evaluation of the Microstructure and Mechanical Properties of Al / Fe3O4 Nanocomposites

Suaad M. Jiaad; Khansaa Salman; Ahmed A. Hussein

Engineering and Technology Journal, 2021, Volume 39, Issue 11, Pages 1632-1638
DOI: 10.30684/etj.v39i11.2080

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.

The Influence of Ultrasonic Impact Peening on the Mechanical Properties of Similar Friction Stir Welded Joints of AA 7075-T73

Abdul Ameer H. Jebur; Samir A. Amin; Ibtihal A. Mahmood

Engineering and Technology Journal, 2021, Volume 39, Issue 9, Pages 1345-1351
DOI: 10.30684/etj.v39i9.1725

The purpose of this study is to study the ultrasonic peening influence upon the mechanical properties of the welded joints of 3 mm AA 7075-T73. Friction stir welding (FSW) was carried out by using milling machine and cylindrical tool with tapered pin. The used welding parameters were 710 rpm , 35 mm min for rotational and travel speed , respectively .Tensile tests results showed that the welding efficiency was about 60% for welded samples , and this value increased by using one and two lines ultrasonic peening treatment to 74% , and 71% , respectively , this improvement is due to generating compressive stresses along the surface of welded joints. The microhardness of the welded samples showed that there were fluctuations across the welded centerline and minimum hardness occur in the heat affected zone (HAZ).

Investigating The Effect of Magnetite (Fe3O4) Nanoparticles on Mechanical Properties of Epoxy Resin

Ehab Kaadhm; Khansaa D. Salman; Ahameed Hameed Raja

Engineering and Technology Journal, 2021, Volume 39, Issue 6, Pages 986-995
DOI: 10.30684/etj.v39i6.2063

In this paper, study the effects of magnetite nanomaterial Fe3O4 on the mechanical properties of epoxy. Dispersion of Fe3O4 nanoparticles in the epoxy resin was performed by ultrasonication. The samples of the nanocomposites were prepared using the casting method. The nanocomposites contain epoxy resins as a matrix material incorporated by different weight percentages of magnetite Fe3O4 that varies from 0wt.% to 15wt.% as a reinforcing material. The epoxy with the additive reinforcement materials Fe3O4 was slowly mixed in a sonication bath for 15 minutes, then the mixture poured into silicon molds. Field Emission Scanning Electron Microscopy FESEM and X-ray diffraction spectra XRD were used to characterize the morphological and structural properties of preparing samples and the distribution of Fe3O4 nanoparticles to the epoxy resin. Mechanical testing consists of tensile, hardness shore, and three-point flexural tests were performed on the samples at room temperature according to ASTM standards. The results showed that reinforcement by 15wt.% of Fe3O4 nanoparticles maximizes these mechanical properties of nanocomposites compared with pure epoxy except for the young modulus's preferred weight at 9 wt.%, this is due to aggregation of the additives nanomaterials in epoxy resin above 9 wt.%.

Effect of Adding TiO2on Some Mechanical Properties of Galloy

Osamah A. Khadhair; Rana A. Anaee; Kadhum M. Shabeeb

Engineering and Technology Journal, 2021, Volume 39, Issue 5A, Pages 695-702
DOI: 10.30684/etj.v39i5A.1395

Because of importance the Ga alloys in dental applications, many attempts were  done  to  improve  the  properties  of  this  alloy. The  currentwork involves  addition  of  TiO2nanotube  powder  to  Galloy  to  improve  somemechanical  properties.  These  properties  included  hardness,  compression, and creep. The characterization of prepared TiO2/Galloys with five wt% of TiO2(1, 2, 3, 4, and 5 wt%) was done by XRD and SEM/EDS. The results showed  that  the  hardness,  compression, were  increased  with  increasing percentage  of  added  TiO2,  while  creep  decrease.Some phases  such as β-Sn,  Ag2Ga  and  Ag9In4were  contributed  to  improve  the  properties  of  new TiO2/Galloycomposites.

Effect of Oil – Corrosion on Tensile and Fatigue S-N Curve Properties of AA6061-T6

Hussain J.M. Al-Alkawi; Ghgada A. Aziz; Shmoos R. Mazel

Engineering and Technology Journal, 2021, Volume 39, Issue 3A, Pages 407-414
DOI: 10.30684/etj.v39i3A.298

The present study described the effect of shot peening on mechanical properties and rotating corrosion –fatigue behavior (strength and life) of AA6061-T6. Ultimate tensile strength (UTS) and yield stress (YS) were reduced by 4.6% and 1.24% when immersing the tensile samples in crude oil for 60 days. The values of (UTS) and (YS) were raised from 307 to 316 MPa and from 248 to 254 MPa respectively when treated for 10 min. shot peening (SP). Hardness of oil corrosion samples dropped due to pitting corrosion and slightly raised for SP prior to corrosion samples. Oil corrosion reduced the fatigue strength by (-1.25%). This percentage was enhanced due to SP to 2.377%. SP significantly increased the rotating fatigue life by a factor of 1.19 and 1.3 at (UTS) and (Ys) loads respectively. (SP) technique improved corrosion-fatigue resistance due to producing compressive residual stresses at surface layers.

Influence of Microfibers Additive on the Self-healing Performance of Mass Concrete

Alaa Z. Dahesh; Farhad M. Othman; Alaa A. Abdul-hamead

Engineering and Technology Journal, 2021, Volume 39, Issue 1A, Pages 104-115
DOI: 10.30684/etj.v39i1A.1581

Because cracks are the main problem of mass concrete, this paper investigates an experimental study on the effect of polypropylene microfiber (PPMFs) on self -repair behavior of mass concrete, through study the microstructure, workability, physical, and mechanical properties of mass concrete. PPMFs with a diameter of 18 μm add in different percentages (0, 0.5, 1 and 1.5) % of cement weight. Where the prepared mixture ratio was (1:2:4.8) and the water-cement ratio (W/C) was 0.4. Also, 0.6% of Superplasticizer (SP) % of cement weight to all concrete mixtures was added. In this study, an SEM analysis used to observe the effect of PPMFs on the microstructure of mass concrete, and compressive and flexural strength tests for study the mechanical properties of this. And referring to the analysis and discussion of the results, PPMFs used have changed the microstructure of mass concrete, and have an effective effect on improving compressive strength and flexural strength, and mechanism of sealing the cracks of concrete autogenously. Also, 1% PPMFs (% of cement weight) recorded as the highest addition, which has a positive effect on mass concrete properties to apply it in the construction field.

Effect of ZrO2 Addition on Microstructure and Mechanical Properties of Al-Zn-Mg Alloy Matrix Composite

Israa A. Aziz; Russul S. Bedien

Engineering and Technology Journal, 2020, Volume 38, Issue 12, Pages 1751-1757
DOI: 10.30684/etj.v38i12A.336

Aluminum – based metal matrix composite are widely used in industrial applications compared with conventional and unreinforced alloy. The composite materials usually exhibit a higher strength both at elevated and ambient temperature, as well as wear resistance. The production of composite materials which contain different weight percentage of ZrO2 (0.5, 1.5 and 2.5wt %) by stir casting process. The mechanical properties of the base alloy and composite were evaluated by using tensile and hardness tests. The microstructure inspection by optical microscopy, scanning electron microscope and energy dispersive spectroscopy (EDS) were utilized to study the fracture surface topography. The results represent that the hardness, strength of yield and tensile strength increased with increasing the weight % of ZrO2 to 2.5 % while the elongation decreased. The microstructure inspection by optical microscope shows that the dendrites structure and the particles distribution in matrix without any voids. Furthermore, the grain size refining with the weight percentage of weight reinforcement elevated.

Effect of Tin Addition on Shape Memory Effect and Mechanical Properties of Cu-Al-Ni Shape Memory Alloy

Raad S. Ahmed Adnan

Engineering and Technology Journal, 2020, Volume 38, Issue 8, Pages 1178-1186
DOI: 10.30684/etj.v38i8A.440

This study examines the effect of Sn additions on Cu-14%Al-4.5%Ni shape memory alloy. Sn was added in three different percentages (0.3,1,3) %. The alloys were mechanically tested both in compression test and micro hardness test. Also, a thermo-mechanical test was performed on the alloys. Results showed an increase in the transformation temperature outside the domain and also a better recovery strain with the increase of Sn percentage of 3% Sn addition showed the best results in mechanical properties while the 3% Sn showed a better Shape Memory Properties near to super elastic.

Effect of Filler Metals on Microstructure and Mechanical Properties of GTAW Welded Joints of Aluminum Alloy (AA2024-T3)

Muna K. Abbass; Jihad G. Abd Ul-Qader

Engineering and Technology Journal, 2020, Volume 38, Issue 8, Pages 1236-1245
DOI: 10.30684/etj.v38i8A.1277

This study presents an appropriate filler metal or welding electrode to join aluminum alloy (AA2024-T3) sheet of 3.2 mm thickness with a square butt joint using Gas Tungsten Arc Welding (GTAW) process. This process was carried out at three different welding currents with three various filler metals: ER4047 (12% Si), ER4043 (5% Si), and ER5356 (5% Mg). Experiments were conducted to investigate the microstructure and the mechanical properties. The effect of various filler metals upon the weld joints quality were analyzed via an X-ray radiographic and tensile test. Hardness test, microstructures, SEM, and XRD also conducted to the welded specimens. It was found that the best result was at 100 Ampere with using filler metal (ER5356) which produced the highest strength of 240 MPa in comparison with welded joints with utilizing fillers (ER4043) and (ER4047) having values of 235 MPa and 225 MPa, correspondingly. The hardness results showed that the highest hardness values were at the weld metal for ER4047 and ER4043, then decreased to HAZ and increased in the base metal. While in the case of ER5356, the highest hardness was in HAZ and decreased in the weld metal. The fractography of the fracture surface of the welded joints after the tensile test was analyzed using SEM

Evaluation of Mechanical Properties and Finite Element Modeling in Friction Stir Welding of C12200 Copper Alloy to C36000 High-Leaded Brass Pipe

Ahmed A. Akber; Ali A. Khleif; Abbas N. Hasein

Engineering and Technology Journal, 2020, Volume 38, Issue 8, Pages 1106-1116
DOI: 10.30684/etj.v38i8A.602

In systems transporting fluids like petrol, water, or any fluids. Copper and brass pipes are used because of the capability to resist corrosion. The copper alloys can be welded by several methods like arc, resistance, friction welding, and gas methods and they can be readily soldered and brazed. In the present study, mechanical properties and finite element modeling evaluation for friction stir welding of two dissimilar pipes (C12200 copper alloy pipe with C36000 copper alloy pipe). During this study six parameters were used where rotation speed of (775,1000,1300 and1525rpm), welding speed of 1.7 mm/min, axial force of 8.5KN, with a CW direction of rotation, and zero degree of tilt angle, using a threaded cone geometry of the tool. The results showed that the best weld quality was in case when the speed of rotation was 1525 rpm

Study of Mechanical Properties of Carbon Steel Plate SA-516 Gr. 70 Welded by SAW Using V-Shape Joint Design

Samir A. Amin; Mohannad Y. Hanna; Abdulaziz S. Khider

Engineering and Technology Journal, 2020, Volume 38, Issue 2, Pages 152-165
DOI: 10.30684/etj.v38i2A.269

Submerged arc welding (SAW) is a fusion type welding and it is considered one of the most important welding types due to its inherent capabilities of high welding speed, high deposition rate, welding large thickness plates owing to its deep penetration characteristic and many other advantages. In this study, the goal was to investigate the effect of welding parameters, namely (welding current and welding speed) as well as the joint design on the mechanical properties (yield stress, bending force on the face of the weldment and hardness of the weld metal. Experiments were conducted employing Design of Expert (DOE) software and Response Surface Methodology (RSM) technique. The experiments were conducted by welding ASME SA-516 Gr. 70 steel plate with dimension (300 mm × 150 mm × 10 mm) depending upon the design matrix developed via the DOE. Results manifested that the optimum process parameters for maximum yield stress, maximum bending force and minimum hardness were at (425 amps) welding current and (35 cm/min) welding speed, where the arc voltage was held constant at (37 volts). The optimum values for the yield stress, bending force and hardness were (474.447 MPa, 36.997 kN and 150 HV), respectively. Finally, it was found that the predicted and experimental results of yield stress, bending force and hardness agree very well according to the ultimate error (1.05%, 1.92%, and 4.25 %), respectively.

The Effects of Anodizing Process on the Corrosion rate and Fatigue Life of Aluminum Alloy 7075-T73

Ibrahim M. AL-Sudani; Samir A. Al-Rabii; Dhafir S. Al-Fattal

Engineering and Technology Journal, 2020, Volume 38, Issue 1, Pages 34-42
DOI: 10.30684/etj.v38i1A.1594

This research aims to study the effect of using the anodizing process on the corrosion rate, mechanical properties as well as the fatigue life for aluminum alloy (7075-T73), which is one of the most commonly used aluminum alloy in production of aircrafts, vehicles and ships structures. The anodizing process was employed through using sulfuric acid for time (20) min in a salty atmosphere. The mechanical properties and fatigue life of the AA7075-T73 were obtained before and after the anodizing process. All the results were listed in detailed tables and figures for comparison purpose. Generally, these results showed a decrease in corrosion rate by (155.06%) in comparison with untreated, an increase in hardness by (21.54%) and a slight decrease in fatigue life by (7.7%) due to anodizing for a time of 20 min at the stress level of (σa = 491.10 MPa). It was concluded that this technique could be applied on other aluminum alloys in order to know the magnitude of change in the mechanical characteristics and their fatigue life.

Recycling of Sewage Sludge Ash in Polymer Structures

Mohamad Alsaadi; Aseel B. Al-Zubaidi; Mukhallad Haider; Hasanain Hashim

Engineering and Technology Journal, 2019, Volume 37, Issue 3C, Pages 311-318
DOI: 10.30684/etj.37.3C.2

In this study sewage sludge ash (SSA) particles were used as filler in the polyester resin to fabricate particulate composites with various filler contents of 0, 1, 2, 3, 4, 5, 6 and 7 wt%. The tensile, flexural, impact, hardness, chemical composition and scanning electron microscope tests wear done on the samples in accordance with ASTM standards. The results were improved at the particle content of 5 wt% for the tensile and flexural strength and then showed reducing trend with extra particle addition. Tensile and flexural modulus values of the particulate polyester composites significantly enhanced compared with the unfilled polyester composite. Energy Dispersion Spectrometry (EDS) results showed that the SSA contains elements and oxides which may increase adhesion force with polymer. In spite of the particle content of SSA that used with polymer to produce various structures for different applications was low, this study approved that using of SSA can protect the environment due to increasing the amount of SSA can affect the environment badly in addition to produce cheaper polymer composite for industrial applications.

Optimization Using Taguchi Method for Physical and Mechanical Properties of Bio Mimicking Polymeric Matrix Composite for Orthodontic Application

Jenan S. Kashan

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 181-187
DOI: 10.30684/etj.37.5A.5

This work take in consideration the application of Taguchi optimization methodology in optimizing the parameters for processing (composition, compounding pressure) and their effects on the output physical (Density and true porosity) properties and mechanical(fracture strength and microhardness) properties for the Nano HA,Al2O3 fillers reinforced HDPE hybrid composite material for orthodontic application. An orthogonal array of the Taguchi approach was used to analyses the effect of the processing parameters on the physical and mechanical properties. On the other hand, the surface roughness and particle size distribution were also calculated to study their effect on the output properties. The result shows that the Taguchi approach can determine the best combination of processing parameters that can provide the optimal physical and mechanical conditions, which are the optimum values (the optimum composition was15HA/ 5Al2O3/80HDPE, and optimum compounding pressure was102 MPa.