Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Tensile Strength


The Effect of Infill Pattern on Tensile Strength of PLA Material in Fused Deposition Modeling (FDM) Process

Maria F. Jasim; Tahseen F. Abbas; Abdullah F. Huayier

Engineering and Technology Journal, 2022, Volume 40, Issue 12, Pages 1711-1718
DOI: 10.30684/etj.2021.131733.1054

Fused deposition modeling (FDM) is an additive manufacturing (AM) process often used to build geometrically complex prototypes and parts. It is becoming more popular since it improves products by eliminating the need for high-priced equipment. Materials, printing methods, and printing variables all impact the mechanical characteristics of printed items. The process parameters of FDM affect the parts' quality and functionality. This study examines the influence of different infill patterns on test specimens made of polylactic acid (PLA) tensile strength. Total of 10 different infill patterns (IPs): Grid, Lines, Triangles, Tri-Hexagon, Cubic, Gyroid, Zig-zag, Concentric, Octet, and Cubic subdivision were taken as process variables. Samples were printed using processing parameters (speed 60 mm/s, layer height 0.1 mm, infill density 80%, extruded at 200◦C). The ASTM D638 tensile test was used to determine the tensile strength based on this printing parameter. According to tensile test results, the infill pattern significantly affects the tensile strength. The results showed that the concentric infill pattern has a higher tensile strength of 32.174 MPa, whereas the triangles infill pattern has a lower tensile strength of 20.934 MPa.

Development the Mechanical Properties of the Acrylic Resin (PMMA) by Added Different Types of Nanoparticles, Used for Medical Applications

Sura H. Ahmed; Waffa M. Salih

Engineering and Technology Journal, 2022, Volume 40, Issue 1, Pages 166-171
DOI: 10.30684/etj.v40i1.2017

This research is studying the effect of reinforcement the acrylic resin (PMMA) by two types of nanoparticles, which included: Walnut shell (WSP) and Talc particles (TP) that practical sizes are (40.8 and 29.2 nm) in individually form, and utilize at three various concentrations (0.1, 0.2 and 0.3wt.%), to improve in the mechanical properties of composite materials. The results showed that the Tensile and Hardness shore D properties became better with increasing the concentration of nanoparticles. The highest value of (tensile strength, modulus of elasticity and elongation at break) was (28 MPa. 1.28 GPa and 2.35%) for (PMMA: 0.3% WSP) composite specimens. And the highest value of hardness shore D was (77) for (PMMA: 0.3% WSP) composite specimen.

Flexural Performance of Reinforced Concrete Built-up Beams with SIFCON

Ghazwan K. Mohammed; Kaiss F. Sarsam; Ikbal N. Gorgis

Engineering and Technology Journal, 2020, Volume 38, Issue 5, Pages 669-680
DOI: 10.30684/etj.v38i5A.501

The study deals with the effect of using Slurry infiltrated fiber concrete (SIFCON) with the reinforced concrete beams to explore its enhancement to the flexural capacity. The experimental work consists of the casting of six beams, two beams were fully cast by conventional concrete (CC) and SIFCON, as references. While the remaining was made by contributing a layer of SIFCON diverse in-depth and position, towards complete the overall depths of the built-up beam with conventional concrete CC. Also, an investigation was done through the control specimens testing about the mechanical properties of SIFCON. The results showed a stiffer behavior with a significant increase in load-carrying capacity when SIFCON used in tension zones. Otherwise high ductility and energy dissipation appeared when SIFCON placed in compression zones with a slight increment in ultimate load. The high volumetric ratio of steel fibers enabled SIFCON to magnificent tensile properties.

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.

Multi-Objective Optimization of Friction Stir Welding for Aluminum Alloy (2024-T3)

Abbas K. Hussein; Laith K. Abbas; Ahmed A. Seger

Engineering and Technology Journal, 2020, Volume 38, Issue 2, Pages 185-198
DOI: 10.30684/etj.v38i2A.280

In this research, a multi-response optimization based on Taguchi method is proposed for friction stir welding (FSW) process for (2024-T3) aluminum alloy. Three different shoulder diameters of tools with tapered pin geometry of (12, 14 and 14 mm) with variable rotation speed (710, 1000 and 1400 rpm) and welding speed of (40, 56 and 80 mm/min), three different tilting angles of (1, 2 and 3 degree) and three welding direction of (1, 2 and 3 passes). The results of this work showed the single optimization by using (Taguchi method) at the optimum condition for the tensile strength and yield strength were (365 MPa) and (258 MPa) respectively; at the parameters: shoulder diameter (14 mm), rotation speed (1400 rpm), linear speed (40 mm/min), tilting angle ((3°) for tensile strength and (1°) for yield strength) and welding direction (3 passes). The results of multi-response optimization for (FSW) process at the optimum condition for tensile strength and yield strength were (371 MPa) and (268 MPa), respectively; at the parameters: shoulder diameter (14 mm), rotation speed (1400 rpm), linear speed (40 mm/min), tilting angle (3°) and welding direction (3 passes).

Some Mechanical Properties of Polymer Matrix Composites Reinforced by Nano Silica Particles and Glass Fibers

Sudad Younis; Jawad K. Oleiwi; Reem A. Mohammed

Engineering and Technology Journal, 2018, Volume 36, Issue 12A, Pages 1283-1289
DOI: 10.30684/etj.36.12A.10

This research studied the effect of nano silica particles on wear behavior test , ultimate tensile strength ,impact strength, fracture toughness and hardness shore D of specimens composite material. The hand-lay-up method is used to preparation of specimens established from unsaturated polyester resin matrix reinforcement with 4% weight fraction glass fiber (chopped / woven) mat and 1%, 3%, 5% weight fraction of nano silica particle. The nano silica particles used in this study has an average size of (less than 45nm). The results showed that the specimen (up+4% woven glass fiber+5% nano SiO2) gives better mechanical properties include ultimate tensile strength, impact strength, fracture toughness and hardness shore D (110 MPa, 13.7 K.J/m2, 18.92 MPa.m1/2, 85 shore D) respectively,when compare other specimens. The wear rate decreased from (22.5×10-4 cm3/N.m) for specimen (pure unsaturated polyester resin) to (0.18×10-4 cm3/N.m) for specimen (UP+4% woven glass fiber +5% nano SiO2) under parameter 7N (load), 15 minutes (sliding time), 2m/s (sliding speed) and (7 cm) sliding distance.

Effect of Waiting Time before Re-vibration on Mechanical Properties of Fiber Reinforced Concrete

Aseel A. Abdulridha

Engineering and Technology Journal, 2018, Volume 36, Issue 7A, Pages 748-758
DOI: 10.30684/etj.36.7A.7

A knowledge of the concrete vibration after casting have led to improve the mechanical properties of concrete, reduce the deformations due to creep and shrinkage and reduce the concrete permeability. At the Structural and Material Laboratories- Building and Construction Engineering Department, University of Technology, series experimental tests on prisms, cubes and cylinders were carried out to investigate the effect of waiting time after initial vibration on the flexural-tensile strength, compressive strength and splitting tensile strength of fiber reinforced concrete. The variables considered in this study were; the amount of steel fiber and waiting time after initial vibration. The test results showed that the concrete prisms without steel fiber show approximately linear behavior till the maximum flexural-tensile load due to brittle behavior of concrete. The maximum improvement in flexural-tensile strength of concrete prism occurs after the initial setting of concrete i.e after 90 minutes of waiting time. The re-vibration after time period increase the stiffness of concrete prism in case of presence of steel fiber compared with the prisms initially vibrated only. The modulus of rupture of concrete prism increased with the increasing of steel fiber content for all waiting time before re-vibration.

Effect of Addition CuO Nanoparticle to Quenching Media on Properties of Medium Carbon Steel

J.H. Mohmmed

Engineering and Technology Journal, 2017, Volume 35, Issue 9, Pages 894-898
DOI: 10.30684/etj.35.9A.4

In current work the effect of addition CuO nanoparticles to the polyalkylene glycol (PAG) water solution quenching media on some properties of medium carbon steel was examined. Five cooling media was used to quenching the steel: water, 5 and 10 % water solution of polyalkylene glycol, and 5 and 10 % water solution of polyalkylene glycol with addition of 1% of CuO nanoparticles. In addition, in this study, the cooling curves for these media and the properties of tensile and affect for quenched and unquenched medium carbon steel were studied and evaluated. The results showed that the addition of CuO nanoparticles strongly improve the quenching media features and contribute to reduce water quenched sample defects (such as distortion and cracking), while at the same time still maintaining the desired mechanical property improvements. The experimental observations indicate that samples quenched 5% polyalkylene glycol water solution of with 1% CuO nanoparticles brought the best combination of mechanical properties.

Improvement, the Performance of Polyurethane (PUR), Y-290 Resin as Coating of Oil Pipeline by Using Multi-Walled Carbon Nanotubes (MWCNTs)

S.A. Awad; E.M. Khalaf

Engineering and Technology Journal, 2017, Volume 35, Issue 8, Pages 845-848
DOI: 10.30684/etj.35.8A.10

In this study, polyurethane epoxy-Y290 (PUR-Y290) as a matrix material was reinforced by 1%MWCNTs. Polyurethane is a thermoset polymer and using for several applications particularly as coatings of gas and oil pipeline. Polyurethane uses as a liquid coating against the corrosion, and that is caused by the direct exposure for long periods of UV irradiation and humidity. The nanocomposites were prepared by adding 1wt% MWCNTs to polyurethane and mixed by using an ultrasound mixer. Polyueethane-1%MWCNTs composite sample was exposed to accelerate weathering (UV irradiation coming from sunlight, moisture, and salt water spray) during the exposure to different durations 6 months, 12 months and 24 months. Exposed and unexposed samples were investigated and evaluated by thermal and mechanical tests.It was found that the incorporation 1.0%wt of MWCNTs filler, enhanced the thermal stability and improved the mechanical properties during the exposure for long-term life to accelerated weathering conditions, compared with polyurethane coating without MWCNTs filler. These results indicated that polyurethane (liquid coating) nanocomposites have a higher resistance to environmental condition and give more protective against corrosion of oil pipelines and applied as coatings by spray method to protect the oil pipeline surfaces from environmental conditions.

Preparation and Characterization of PMMA-HDPE and HDPE-PMMA Binary Polymer Blends

S.I. Salih; A.M. Al.gabban; A.H. Abdalsalam

Engineering and Technology Journal, 2017, Volume 35, Issue 4, Pages 311-317
DOI: 10.30684/etj.35.4A.2

A comparison was made on the mechanical characteristics of binary blends polymethylmethacrylate/ high density polyethylene (PMMA-%HDPE) and vice versa. Analysis of morphology by SEM has been also accomplished. Preparation of polymer blends was performed using melt mixing method by an extruder. Tensile results showed that binary polymer blends (PMMA-%HDPE) indicated an increment in ultimate tensile strength, elastic modulus and shore D hardness compared to (HDPE-%PMMA). The blend of 95%PMMA- 5%HDPE shows superior mechanical properties. SEM results indicated that the prepared blends are not fully compatible with some separated phases of the second polymer dispersed in the matrix.

Study the Mechanical and Physical Properties of Polyester Composite Reinforced by Multi Layers

Fadhil Abbas Hashim; Mohammed Sellab Hamza; Reham Raad Abdulla

Engineering and Technology Journal, 2016, Volume 34, Issue 9, Pages 1834-1843
DOI: 10.30684/etj.34.9A.10

In this research, a laminate composite has been prepared, using unsaturated polyester resin (UP) as a matrix reinforced with Kevlar fibers in different number of layers, glass fibers were added to the optimum product, by replacing one of the layers of Kevlar Fibers with a layer of Glass Fibers. Hand Lay-up method was used to prepare the test samples. To evaluate the composite material properties, tensile, hardness, impact, optical microscope tests were done.
The results of composite made of polyester reinforced with Kevlar Fibers show that the mechanical properties (Tensile strength, Modulus of elasticity, Hardness, Impact strength) increase with increasing the number of reinforced layers.
The best experimental values ofthe mechanical properties (Tensile strength, Modulus of elasticity, Hardness, Impact strength) were (190 MPa, 1.72 GPa, 79.25, and 68.75KJ/m2) respectively, for composite with three layers of Kevlar Fibers and then followed by composite with the sequence of layers (kevlar-glass-kevlar) and its mechanical properties (Tensile strength, Modulus of elasticity, Hardness, Impact strength) were (175.5 MPa, 1.69 GPa, 80, and 59.1 KJ/m2) respectively, Optical microscope shows welldistribution ofreinforcedlayers in composite.

Effect of Degassing Process of Squeeze Casting Aluminum Alloy on Tensile Strength Under Different Pressures

Hussain J. Al-alkawi; Dhafir S. Al-Fattal; Samih K. Al-najjar

Engineering and Technology Journal, 2015, Volume 33, Issue 2 engineering, Pages 320-330
DOI: 10.30684/etj.2015.101900

Degassing technique currently applied to cast aluminum alloys due to its technological and economic advantages. The present work aimed to study the effect of degassing technique of cast aluminum alloy (LM2) under different pressures using squeeze casting process. Inert argon gas was pumped into the molten aluminum with flow rate (2,5-5-7)l/min. at constant pumped duration (5min.). Different applied pressures were used(17, 35, 52) MPa. The test was performed at room temperature. The physical and mechanical properties of degassed samples were measured and compared with non-degassing (ND) samples. The results showed that the best condition of degassing is found at 2.5 l/min flow rate and 35 MPa applied pressure. It was found that a slight difference is observed for the density and the lowest value of porosity was obtained at 2.5 l/min flow rate and 52 MPa applied pressure.

Effect of Using Windows Waste Glass as Coarse Aggregate on Some Properties of Concrete

Abdelmaseeh Bakos Keryou; Gailan Jibrael Ibrahim

Engineering and Technology Journal, 2014, Volume 32, Issue 6, Pages 1519-1529
DOI: 10.30684/etj.32.6A.14

In this experimental study, local waste glass (WG) gathered from Turkey-made windows glass has been used as a partial replacement of coarse aggregates with 0, 20, 25, and 30% percentages of replacement by weight. Some mechanical and other properties of the concrete, produced this way have been studied at both fresh and hardened stages.
The experimental results obtained from testing the specimens prepared from concrete mixes with water/cement ratio equal to 0.5, showed that using WG resulted in decreasing the slump and fresh density due to angular grain shape, whereas the compressive, splitting, and flexural strengths noticeably enhanced. Tests revealed that with increasing the WG percentage the strengths gradually increase up to a given limit beyond which they decrease. The maximum effect was reached at 25% percentage of replacement. At this percentage the increases in the compressive, splitting tensile and flexural strengths at 28-day age were 30, 38 and 31 %, respectively. The results of this study indicate a considerable economical effect from using the optimum percentage of WG (25%) as partial replacement of coarse aggregate.

Modeling of Arc Metal Welding Process of Low Carbon Steel (304)

Majid Hameed Abdul Majeed

Engineering and Technology Journal, 2014, Volume 32, Issue 3, Pages 643-652
DOI: 10.30684/etj.32.3A.7

This work includes an investigation of the effect and optimization of welding parameters on the tensile strength in the arc metal welding process. The experimental studies were conducted under varying welding currents, wire diameters, and heat input. The settings of welding parameters were determined by using the Taguchi experimental design method. The level of importance of the welding parameters on the tensile strength is determined by using analysis of variance (ANOVA). The optimum welding parameter combination was obtained by using the analysis of signal-to-noise (S/N) ratio. The tensile strength model was formulated based on Analysis of Variance (ANOVA) using Minitab® statistical package. The experimental results confirmed the validity of the used Taguchi method for enhancing the welding performance and optimizing the welding parameters in the arc metal welding process.