Main Subjects : Material
Properties of Welded Copper Tubes Fabricated Via Friction crush Welding
Engineering and Technology Journal,
2022, Volume 40, Issue 6, Pages 0-0
DOI:
10.30684/etj.v40i6.2292

Structural Characterization of (Mg(1-x)pbxO)-NPs by Modified Pechini Method
Engineering and Technology Journal,
2022, Volume 40, Issue 6, Pages 0-0
DOI:
10.30684/etj.v40i6.2147

Preparation of CuO/ZnO Nano-Particles Using Sol-Gel Technique and Studying the Characterization
Engineering and Technology Journal,
2022, Volume 40, Issue 6, Pages 0-0
DOI:
10.30684/etj.v40i6.2104

Preparation of Metakaolin Based Geopolymer Foam Using a Combination of Na and K Types of Alkali Activators
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.
Effect of the Waste Rubber Tires Aggregate on Some Properties of Normal Concrete
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.
Improve the Corrosion Resistance of the Copper-Zinc Alloy by the Epoxy-WO3 Nanocomposite Coating
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.
Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC
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 (S.cm) and it was 0.214(S.cm) 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.
Preparation and Characterization of Polymer Blend and Nano Composite Materials Based on PMMA Used for Bone Tissue Regeneration
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.