Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Tensile strength


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.2021.168187

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).

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

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

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

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.

Tensile Properties Distribution of Coir Natural Fiber Using Weibull Statistics

Ahmed Mudhafar Hashim; Jawad Kadhim Oleiwi

Engineering and Technology Journal, 2016, Volume 34, Issue 6, Pages 1080-1087

In current time, most of the composites based on polymer resins reinforced with natural fibers than synthetic fibers for environmentally friendly consideration. This work investigate the study of tensile properties distribution of coir natural fiber by using Weibull statistics to quantify the degree of variability in fiber strength. Single-fiber tensile and microscopy tests were performed to determination the tensile properties (tensile strength and modulus of elasticity) and fiber crosssectional
area respectively. The experimental results showed that the coir natural fiber have a good tensile strength and modulus of elasticity of 89.91–237.46 MPa and 2.55-8.78 GPa respectively. The Weibull distribution indicates that the coir natural fiber have a high degree of linearity of R2 = 0.942. The Weibull modulus for corn fibers was β = 3.650 , gives a good variability in tensile strength.

Investigate and Comparison Effect add Amorphous and Crystalline - Nano SiO2 on Properties of Concrete

Rami Joseph Aghajan Sldozian

Engineering and Technology Journal, 2015, Volume 33, Issue 3, Pages 547-555

In this paper, the study included the comparison between amorphous silica and crystalline silica (quartz), and with nano scale size, two types of silicawere added to concrete by ratios (5%, 10%, 15%, and 20%) as a replacement by the weight of cement. Destructive and non-destructive tests wereconducted on the specimens, the results show in destructive test the compressive and tensile strength increase in 15%wt addition ratio in both types of silica, but in amorphous silica was high than in quartz.The results of non-destructive tests show in (Schmidt Hammer) the 15% ratio in both kinds of silica show high hardness than other ratios. Ultra sonic (pules velocity) test, noted the better quality was in 15% ratio in amorphous silica and also show fastest pules velocity.

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

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.

Creep Behavior in Fiber-Reinforced Epoxy (DGEBA) Composites

Lubna Ghalib

Engineering and Technology Journal, 2013, Volume 31, Issue 1, Pages 12-25

The composite material was prepared by reinforcing the epoxy with E-glass fiber. The creep and flextural test were measured in this work for one and two layer of E-glass fiber with volume fraction rate of (10%, 20%, 30%, and 40%) in orientation of (0-90o) immersed in epoxy (DGEBA) resin with total thickness of 4mm. The tests were done at different temperature levels from (25 to 55)Co for creep test. The results had revaluated showing that the creeping properties of this composite materials will be improved with increasing the volume fraction layer of fiber at different temperature levels with constant stress. Creeping increases when the temperature increases and decreases with increasing of the number of layers and volume fraction of fiber. The creep constant increases with increasing the temperature up to 45Co then the creep constant down. The creeping energy of epoxy E-glass (epoxy composite) increases with increasing the volume fraction rate of E-glass fiber.

Using of Taguchi Method to Optimize the Casting of Al–Si /Al2O3 Composites

Osama S. Muhammed; Haitham R. Saleh; Hussam L. Alwan

Engineering and Technology Journal, 2009, Volume 27, Issue 6, Pages 1143-1150

Taguchi method is a problem – solving tool which can improve the performance
of the product, process design and system. This method combines the experimental and
analytical concepts to determine the most influential parameter on the result response for
the significant improvement in the overall performance. In this research Al–Si /Al2O3
composites was prepared by vortex technique using three different parameters, stirring
time, stirring speed, and volume fraction of the reinforcement particles. A tensile and
hardness tests were done for the resulted castings. The primary objective is to use
Taguchi method for predicting the better parameters that give the highest tensile strength
and hardness to the castings, and then preparing composites at these parameters and
comparing them with the randomly used once. The experimental and analytical results
showed that the Taguchi method was successful in predicting the parameters that give
the highest properties and the volume fraction was the most influential parameter on the
tensile strength and hardness results of castings